Audi | A6'05 323 | Specifications | Audi A6'05 323 Specifications

323
Vorsprung durch Technik www.audi.co.uk
Service Training
Audi A6´05
Self-Study Programme 323
All rights reserved.
Subject to technical
change.
Copyright
AUDI AG
I/VK-35
Service.training@audi.de
Fax +49-841/89-36367
AUDI AG
D-85045 Ingolstadt
Technical release 01/04
Printed in Germany
A04.5S00.06.20
Preface
The new Audi A6 – the most progressive vehicle takes the lead
Design and performance are the main driving
elements on its way to the top position.
Furthermore, the new Audi A6 embodies the
consequent continuation of the familiar Audi brand
values, sports appeal, progressiveness and intrinsic
quality, which are evident in the fourth generation
of this sporty business limousine.
”Vorsprung durch Technik” – this guiding principle is
consistently maintained in the new Audi A6´05
through its innovative technologies.
Highly dynamic chassis technologies are combined
with consumption-optimized drives with the latest
FSI or TDI technology for greater driving pleasure.
Rounded off with servotronic and the 6-stage
tiptronic system with sport programme, the new
Audi A6´05 has optimal driving dynamics as well a
sporty and comfortable tune-up.
The MMI operating system in the interior of the
vehicle is the central control for the extensive
functionalities. The driver-orientated cockpit design
provides a perfect workplace, which is both stylish
and sophisticated. The high functionality is
emphasized by the customer-orientated features in
the safety and convenience function areas.
Self-study programmes for the Audi A6´05
SSP 323 Audi A6´05
–
–
–
–
Introduction to the vehicle
Body technology
Passenger protection
Air conditioning
Order No.:
A04.5S00.06.20
323_057
SSP 324 Audi A6´05 Chassis
–
–
–
–
–
Front axle technology
Rear axle technology
Steering system
ESP
Electromechanical parking brake EPB
Order No.:
A04.5S00.07.20
323_058
SSP 325 Audi A6 ´05 Engines
and Gears
–
–
–
–
–
3.0 V6 TDI Common Rail
3.2 litre V6 FSI
Manual gearbox 01X, 02X, 0A3
6-stage automatic transmission 09L
Multitronic 01J
Order No.:
A04.5S00.08.20
323_059
SSP 326 Audi A6 ´05 Electrics
–
–
–
–
Networking
Bus topologies
Convenience electrics
Infotainment
Order No.:
A04.5S00.09.20
323_056
The Self-Study Programme provides information on the fundamentals of the design and function of new
vehicle models, new vehicle components or new technologies.
The Self-Study Programme is not a Workshop Manual!
Specified values serve only to make the information easier to understand and relate to the software version
that was valid at the time the Self-Study Programme (SSP) was created.
For maintenance and repair work, please make sure to use the current technical documentation.
Reference
Note
Contents
Chapter 1 Introduction
Product highlights. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 6
Dimensions. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
Chapter 3 Passenger protection
Safety system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Airbag control unit J234 . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Data exchange. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Sensors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Belt warning. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Airbag . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Airbag disabling key switch, front passenger side E224
Seat belts and belt tensioners N153 and N154 . . . . . . . .
Active head restraints . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Battery cut-off relay J655 . . . . . . . . . . . . . . . . . . . . . . . . . . .
Seat occupied recognition, not for USA . . . . . . . . . . . . . . .
Seat occupied recognition for USA market . . . . . . . . . . . .
Seat occupied recognition control unit J706 . . . . . . . . . .
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. 20
. 22
. 23
. 24
. 26
. 27
. 31
. 31
. 33
. 34
. 36
. 37
. 40
Chapter 5 Engine / Gearbox
Overview of available engine / gearbox combinations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 46
Chapter 7 Electrics
Bus topology . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 54
In/outputs on control units J393, J519 and J520 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 56
Contents
Chaper 2 Body
Body shell / connection technology
Materials . . . . . . . . . . . . . . . . . . . . . . . .
Blanks . . . . . . . . . . . . . . . . . . . . . . . . . .
Assemblies . . . . . . . . . . . . . . . . . . . . . .
Bumpers . . . . . . . . . . . . . . . . . . . . . . . .
Trailer coupling . . . . . . . . . . . . . . . . . .
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..8
. 10
. 12
. 14
. 16
. 17
VAS 5053 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAS 5051 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
VAS 5053/20. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Recording the working time using the VAS 5051 / 5052
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. 42
. 43
. 44
. 45
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. 48
. 48
. 49
. 50
. 51
. 51
. 52
. 53
. 53
Chapter 4 Diagnosis
Chapter 6 Chassis
Overview . . . . . . . . . . . . . . . . . . . . . . .
Front axle . . . . . . . . . . . . . . . . . . . . . .
Rear axle . . . . . . . . . . . . . . . . . . . . . . .
Wheel brake . . . . . . . . . . . . . . . . . . . .
ESP . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Electromechanical parking brake –
Steering system. . . . . . . . . . . . . . . . .
Wheels / tires . . . . . . . . . . . . . . . . . . .
Tire pressure control system . . . . .
....
....
....
....
....
EPB
....
....
....
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Chapter 8 Air conditioning
Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 58
Convenience automatic air conditioning and convenience automatic
air conditioning plus. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 60
CAN networking . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 61
Components in the Audi A6 ´05 air conditioning unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 64
Replacing components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 66
Control motor versions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 68
In/output signals at Climatronic control unit J255 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 69
Additional electric air heater. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 71
Auxiliary / additional heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 72
Air conditioning diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 74
Special tools for the Audi A6´05 air conditioning system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 75
Introduction
Product highlights
The product features which support the new Audi A6´05 on its way to the top, can be summarised as follows:
One wing is the design, the other wing is the car’s performance.
Performance
Design
Power trains
Quality
– Power-controlled power trains, better than
competition
– New FSI technology from motor racing
– New TDI technology common rail II with
Piezo injectors
– Quattro:
– Multitronic
– 6-stage Tiptronic
– Wide selection of motors and gearboxes
– Use of intrinsically valuable materials
(aluminium, wood, leather)
– High-quality standard equipment (light-rain
sensor, aluminium trim, active headrests in front,
servotronic, EPB, fog headlights, ...)
– Highest safety standards (5 star Euro NCAP)
– Small gap widths, even joints
Package
Innovation
–
–
–
–
–
–
–
FSI
Common rail II with piezo injectors
Expanded ESP
MMI as standard
Integrated driver cockpit
Electromechanical parking brake
Advanced key, adaptive light, LED brake lights,
comfort climate control plus
– Premium vehicle dimensioning
– Rear knee room 8 cm
– Wider shoulder widths, front +23 mm,
rear +6 mm
– Front headroom +7 mm
– Superior luggage compartment volume (546 l) for
front-wheel and quattro models
– Wheelbase +9 cm
Exterior/Interior
Driving dynamics
– New dynamic chassis with trapezoidal-link rear
axle and redesigned four-link front axle
– Increased body stiffness + 35 %
– Larger tyre diameter
– Servotronic now standard
– Wider tread widths, front +7 cm, rear +6 cm
– Excellent rear downforce for safe handling
– Completely new line design (roofline, shoulder
line, dynamic line)
– Dynamic joint matching
– Coupe-like shape
– Separation edge on rear end
– Single frame
– Double-pipe exhaust for front-wheel and
quattro models
– Full exterior surface painted
Performance
Driving dynamics
Power trains
Innovation
The most
progressive car
takes the lead
Exterior/Interior
Quality
Package
Design
323_038
6
Dimensions
The new Audi A6´05 impresses with its imposing external dimensions.
The vehicle length has been increased to 4.92 m, which corresponds to an increase of 12 cm compared to its
predecessor. The vehicle width has been increased by 4.5 cm to 1.86 m. The height of the new A6´05 has been
increased by 0.8 cm to 1.46 m. The new Audi A6´05 has grown. For the dimensions, please refer to the
diagrams.
323_034
7
Body
Body shell / connection
technology
The main objectives during the development of the
new Audi A6 body design were the realization of
high passive safety characteristics and improved
rigidity values as a precondition for optimizing
vibration damping characteristics.
In spite of the greater demands compared with
the previous model, the body weight has been kept
at the same level.
323_001
A further task during the body development process
is to minimize the number of necessary body
versions.
The new A6´05 uses four body shell versions:
– rigid rear panel
– with opening for loading
– without sliding sunroof
– with sliding sunroof
A standard rear section is used for the front-wheel
drive and quattro vehicles.
8
In addition to classic resistance spot welding, the
following connecting techniques are used on the
new A6´05 body shell:
– Spot welding bonding
– Punch riveting
– Clinching (bonnet & rear opening hood)
– Laser soldering
– Laser welding
– as well as MIG soldering
Spot welding bonding, using a high-strength
structural adhesive, is used for particularly
crash-relevant and rigidity determining connections
(length of the bonded seam factor 3 compared with
predecessor).
The Aluminium components are joined to the
galvanized steel sheets by means of punch rivets
and by bonding.
These aluminium-steel connections are used on the
following parts in the body:
– in the plenum chamber front panel
– sill reinforcement (with aluminium extruded
section)
– rigid rear panel with rear shelf
Spot welding bonding
Laser
MIG soldering
323_002
Laser-soldered zero joint
The roof and side panel frame are joined by
laser-soldering.
Roof
Outer side part
Poorly accessible components are joined by
laser-welding.
The laser-welding head is smaller and thus has
greater flexibility than comparable spot welding
tongs.
In addition, the weight can be reduced by reducing
the flange widths.
MIG soldering is used for closed sectional bars
which are only accessible from one side,
e.g. longitudinal floor members.
323_003
9
Body
Materials
In addition to conventional deep-drawing steels, the
following materials are used in the body structure
of the new Audi A6´05:
– High tensile sheet steel
– Special sheet steel
– Aluminium sheets
– Aluminium extruded sections and
– Plastic-ribbed deep-drawing steel component
(hybrid component)
High tensile steels (180 - 300 N/mm²)
Dual-phase steels (340 - 500 N/mm²)
Weight percentage of high-tensile steel sheets
Total:
45 %
Upper section: 42.3 %
Lower section: 46.7 %
Special steel (600 - 900 N/mm²)
Aluminium
Hybrid component
10
High-tensile steel sheets are used especially in
areas which require strengthening and greater
impact resistance.
Special steel sheets are also used in the body
structure, e.g. front wheelhouse cross-member.
The engine bonnet and front mudguards are made
of aluminium.
In addition to the add-on parts in the shell,
aluminium sheets are used in the structure for
large-area components which are not subject to
excessive stress.
Large-volume aluminium extruded sections are
used as sill reinforcements to stiffen the cell
structure in the event of an offset or side crash.
The front roof frame is designed as a hybrid
component in order to reduce the weight.
323_004
11
Body
Blanks
Blanks with different wall thicknesses and material
qualities are used to realize a stress-adapted
material distribution for large-area components
which are subject to high stress.
tailored blanks
tailored-rolled-blanks
hybrid components
12
Laser-welded blanks, so-called tailored-blanks,
are used for
– the front suspension strut cross member
– front floor panels
– inner side section
– rear longitudinal member
– and door inner panels
Tailored-rolled blanks, which have variable rolled
wall thicknesses, have particular advantages.
They can be used to produce continuous material
thickness transitions which meet the local stress
conditions. This technique is used to optimize the
front longitudinal member structure.
In total, a weight reduction of 8 kg (without add-on
parts) was realized through the material selection
being adapted to the respective stress conditions.
An additional weight reduction of 9 kg was realized
by using blanks with different wall thicknesses.
323_005
13
Body
Assemblies
Plenum chamber
One application area for special steel is the chassis
connection in the proximity of the spring and shock
absorber seat.
It was possible to reduce the wall thickness of the
respective parts from 2.5 to 1.4 mm.
The resulting loss of local rigidity was offset by
creating an optimized profile.
In addition, a tailored blank is fitted in the plenum
chamber.
This ensures the highest possible energy
absorption in the event of a crash.
At the same time, the necessary rigidity and
stability are ensured during normal driving.
Transverse rigidity is ensured by a rolled sectional
bar as an additional reinforcement.
Special steel (600 - 900 N/mm²)
tailored blanks
Aluminium
323_031
Wheelhouse
To ensure an optimum introduction of the crash
energy from the front of the car into the passenger
compartment, special steel components were used
in the proximity of the wheelhouse.
323_030
14
B-pillar
Due to the increased requirements regarding the
strength of the B-pillar, a combination of different
materials is used.
– front inner side section (high tensile steels)
– rear inner side section, tailored blank
(dual-phase steels, high tensile steels)
t = 1.35 mm and 0.8 mm
– B-pillar reinforcement (dual-phase steels)
– B-pillar (dual-phase steels)
323_032
15
Body
Bumpers
Front bumper
The bumper on the new Audi A6´05 is painted in the
colour of the car.
It comprises the following components:
– Coating
– Top cover
– Towing lug cover
– Radiator grille with chrome frame
– Fog lamps
– Side air inlet grilles
– Bumper support
The number plate in the radiator grille is integrated
stylishly and harmoniously within the overall
design.
323_006
The bumper support comprises an open aluminium
cross member, which is screwed on to the
longitudinal member using newly developed shear
boxes.
The shear box absorbs the crash energy from all
centrical and slightly diagonal impacts through its
shearing effect.
Expensive damage to the welded vehicle structure
behind it is thus avoided up to a speed of 15 km/h.
In the event of diagonal impacts, the impact energy
is absorbed by the bumper buckling (folding) and
deforming.
The seat for the towing lug is integrated in the
right-hand shear box.
The towing forces are guided centrically into the
longitudinal member.
323_008
16
Rear bumper
The rear bumper assembly comprises the coating,
spoiler, towing lug cover and closing part
components. It is mounted on the vehicle by means
of fixed guides on the body. The bumper support
and the bracket for the bumper support are made of
aluminium and are produced by extrusion
moulding.
Compared to the previous model, the joints on
the A6´05 have been noticeably reduced.
Due to a special adjusting/holding part below the
rear light, the zero joint between the bumper
coating and side part has been reduced to 0.8 mm.
A parking aid and a mechanically swivelling trailer
coupling are available (optional).
323_007
Trailer coupling
The newly developed trailer coupling fitted in
the A6´05 is equipped with a mechanically
swivelling ball rod.
The ball rod swivels around a rotation axis, which is
angled at 45° to the longitudinal axis of the vehicle.
The swivel angle between the swivelled-out towing
position and the idle position behind the bumper
is 180°.
The system is unlocked by means of a handwheel
located in the boot.
323_010
323_009
17
Body
Control unit for trailer detection J345
Arrangement in the vehicle
The basic function of trailer detector control
unit J345 corresponds to the control unit which has
already been in use since the 2001 Audi A4.
To be used in the Audi A6´05, it was upgraded by the
control function for the swivelling trailer coupling.
It now has the additional task of detecting the
locking status of the mechanically swivelling trailer
coupling and indicating this to the driver.
F354
Handwheel
K226
K227
F355
323_035
18
On pulling the handwheel in the boot, the contact
switch on handwheel F354 is closed. On turning the
handwheel, the locking bolt on the trailer coupling
is unlocked mechanically by a Bowden cable and
the contact switch on locking bolt F355 opens.
After being unlocked, the trailer coupling can be
swivelled out/in mechanically. After being swivelled,
it is automatically locked by spring power. The
contact switches return to their initial position.
The control unit cannot differentiate between a
locked, swivelled-in trailer coupling and a locked,
swivelled-out trailer coupling.
The locking state is indicated by two LEDs in the
handwheel for the trailer coupling. When the green
warning lamp for trailer coupling locked (K226)
lights up continuously, it indicates that the trailer
coupling is swivelled in/out correctly.
323_036
The red warning lamp for trailer coupling
unlocked (K227) flashes when the trailer coupling is
not locked. In addition, a message appears on the
central display in dash panel insert J285.
When terminal 15 is switched off, the warning lamp
for trailer coupling locked (K226) switches off if the
tailgate/boot lid is closed or remains open for
longer than 10 minutes. The warning lamp for trailer
coupling unlocked (K227) switches off if the tailgate/
boot lid is closed or remains open for longer than
20 minutes. The respective warning lamp switches
on again when there is a control unit wake-up or a
CAN wake-up.
CHECK
TRAILER
COUPLING
323_033
19
Passenger protection
Safety system
A top-level safety system: The performance target is
to increase the existing high safety level of the
current Audi fleet.
The compliance with current laws and the
completion User tests, in which the new
Audi A6´05 was to gain a top position in the rating
scheme, were only a part of the extensive safety
requirements. In many cases, additional Audi
in-house requirements increase the requirements
which have to be met by the development team.
Particular attention was paid to a high protection
potential in the event of an accident and the
compatibility. Audis's policy of designing vehicles
with high safety specifications is supplemented
by scientifically gained knowledge of the
actual accident and its effects.
For this, the AARU (Audi Accident Research Unit*)
examines crashes involving relatively new
Audi vehicles.
The development team's task is to analyse and
reconstruct accidents and to draw up potential
improvements.
In addition to this, the AARU evaluates the relevant
accident databases.
The safety system in the Audi A6´05 comprises the
following familiar components:
–
–
–
–
–
–
Airbag control unit
Driver and front passenger airbags, two-stage
Front side airbags
Sideguards (head airbags)
Sensors for side crash detection
Front belt tensioners
The Audi A6´05 has the following new components:
– Crash sensors for the front airbag, the so-called
upfront sensors for frontal crash detection
– Battery cut-off relay
– Sensors for side crash detection in the doors
– Switches in the front belt locks
– Seat occupied recognition in the front passenger
seat
The vehicle can be equipped with side airbags at the
rear and a key switch for deactivating the front
passenger airbag with a corresponding warning
lamp (optional).
The safety system in the Audi A6´05 is rounded off
by the active head restraints in the front seats.
The A6´05 thus constitutes a successful example of
an overall vehicle development aimed at protecting
the passengers.
Due to the different demands and legal
provisions which car makers are subject to in
the different markets, the equipment can vary for
the US American market in particular.
* Audi Accident Research Unit
Note
Legend
Observe the respective safety instructions
in the repair guide before carrying out
any work on the airbag system!
E224
E24
E25
Airbag disabling key switch, front passenger side
Belt switch, driver side
Belt switch, front passenger side
G128
G179
G180
Seat occupied sensor, front passenger side
Crash sensor for side airbag, driver side (front door)
Crash sensor for side airbag, front passenger side
(front door)
Crash sensor for side airbag, rear, driver side
Crash sensor for side airbag, rear, front passenger side
Crash sensor for front airbag, driver side
Crash sensor for front airbag, front passenger side
G256
G257
G283
G284
20
G284
G283
K145
PASSENGER
AIRBAG OFF
J623
J285
K75 / K19
AIRBAG
E224
AUS EIN
T16
J533
N95 / N250
N131 / N132
G179
J234
N199
E24
G180
E25
G128
N200
N252
N251
N154
N153
G256
G257
J393
J655
326_002
J234
J285
J393
J533
J623
J655
Airbag control unit
Control unit in dash panel insert
Central control unit for convenience system
Data bus diagnosis interface
Engine control unit
Battery cut-off relay
K19
K75
K145
Warning lamp for belt warning
Airbag warning lamp
Airbag warning lamp, front passenger side, off
(PASSENGER AIRBAG OFF)
N95
N250
N131
N132
N153
N154
N199
N200
N251
N252
Airbag igniter, driver side
Airbag igniter 2, driver side
Airbag igniter 1, front passenger side
Airbag igniter 2, front passenger side
Belt tensioner igniter 1, driver side
Belt tensioner igniter 1, front passenger side
Side airbag igniter, driver side
Side airbag igniter, front passenger side
Head airbag igniter, driver side
Head airbag igniter, front passenger side
T16
Plug-in connection, 16x (diagnosis connection)
21
Passenger protection
Airbag control unit J234
The task of the airbag electronics is to detect vehicle
deceleration and evaluate it so that a collision is
reliably detected. The control unit can detect
frontal, side and tail accidents. In addition, the
electronics also have the task of activating the
respective restraint systems (airbags / belt
tensioners) depending on the type of collision and
its severity and activating the Crash output.
The airbag electronics have the following main
tasks:
– Crash detection (front, side, tail)
– Defined triggering of the airbags, belt tensioners
and battery cut-off
– Defined triggering of the second front airbag
stage
– Evaluation of all input information
– Permanent monitoring of the entire airbag
system
– Independent power supply via capacitor for a
defined time (approx. 150 ms)
– Error indication via failure warning lamp
– Storage of error and crash information
– Notification of a crash event to other system
components via drive CAN or discrete
Crash output (conventional cabling)
– Activate belt warning
In addition to the internal sensors in the control
unit, the external crash sensors are also used to
detect vehicle deceleration during impact.
The electronics can only decide when and which
safety components to activate after all the sensor
information has been evaluated by the control unit
electronics.
If an airbag control unit is replaced, then it must be
coded and adapted to the respective.
These functions can only be peformed by means of
the guided fault finding procedure and a diagnosis
tester which can be used online. The Service
technician needs access (with password) to the
”FAZIT” database at Audi.
If the coding or adaptation is not carried out in the
correct manner, malfunctions can occur in other
vehicle systems such as the ESP, for example.
326_008
22
Airbag warning lamp K75
The airbag warning lamp, which is located in
dash panel insert J285, is triggered via the bus CAN.
If there is no data message from the airbag control
unit, the warning lamp is automatically switched on
from the dash panel insert.
Rear crash detection
In the event of a rear-end crash, the airbag control
unit evaluates the information from the internal
crash sensor and the crash sensors for front
airbags G283 and G284. If their signals exceed a
fixed value, the belt tensioners are ignited and
the battery cut-off relay is activated.
Data exchange
The airbag control unit is integrated within the
drive CAN.
The airbag control unit transmits the following
information on the drive CAN:
–
–
–
–
–
–
–
Trigger warning lamp K75
Activate belt warning
Diagnosis data
Crash signal
Crash information for the actuator test
ESP data
Front passenger airbag disabled (for USA only)
The airbag control unit evaluates the following
information from the data bus:
– Dimming of the airbag warning light
Passenger airbag off
23
Passenger protection
Sensors
Crash sensor
(in the control unit)
The acceleration sensors are arranged in such a way
that both deceleration in the vehicle's longitudinal
axis (x-axis) and deceleration in the vehicle's
transverse axis (y-axis) are detected.
Safety switch
326_015
(in the control unit)
The mechanical safing sensor in the airbag control
unit for the Audi A6‘05 has been replaced
by a micromechanical acceleration sensor.
This sensor also detects the vehicle's deceleration in
the direction of travel (x-axis) and sends this
information to the control unit electronics for a
plausibility check.
326_016
Crash sensors for front airbag G283
and G284
(upfront sensors at front end)
Front airbag crash sensors
The severity of the crash changes the signal, which
the front airbag crash sensor sends to the airbag
control unit. Depending on the signal, a threshold
reduction is activated in the airbag control unit,
which improves the crash detection function and
and thus enables the airbags to be ignited earlier.
A greater protective effect can be attained by
triggering the airbags earlier.
326_009
Crash sensors for side airbag G179
and G180
(in the front doors)
Pressure sensors are now used in both front doors
(new).
The deformation of the vehicle in the event of a side
crash causes a short-term increase in air pressure in
the door. This pressure increase is detected by the
sensor and is forwarded to the airbag control unit.
Front airbag crash sensors
326_007
24
Crash sensors for side airbag, rear,
G256 and G257
(C-pillar)
Both crash sensors for side airbag G256 and G257,
which are fitted near the C-pillar (left and right), are
conventional acceleration sensors, which were
already used for the previous Audi A6 model.
How the crash sensors work
A crash sensor essentially comprises a housing,
evaluation electronics and a micro-mechanical
acceleration sensor.
Basically, the acceleration sensor is structured
like a capacitor.
Some of the capacitor plates are fixed. The
counterparts of these are movable and work like a
seismic mass.
If the seismic mass is pushed into recording
direction during an accident, the capacity of the
capacitor changes. This information is evaluated
by the evaluation electronics and is then digitally
processed and transmitted to the airbag control
unit.
Evaluation electronics
Acceleration sensor
Pressure sensors, on the other hand, react to a
change in pressure conditions. The resistance of the
micromechanical sensor unit is monitored and
evaluated.
326_003
Idle position
Movable capacitor plate
Crash
Direction of detection
Capacitor plate
fixed
Evaluation electronics
326_025
25
Passenger protection
Belt warning
The new Audi A6´05 includes a belt warning function
for both driver and passenger.
After switching on the ignition, the driver's belt lock
switch and the front passenger's belt lock switch
(in conjunction) with the seat occupation sensor on
the front passenger side is evaluated by the airbag
control unit. The control unit recognizes whether
the front passenger seat is occupied on the basis of
the resistance values from the seat occupied sensor.
If the driver or front passenger has not fastened
the seat belt, a warning is given by means of belt
warning warning lamp K19 in the dash panel insert
and an acoustic signal.
Time diagrams for the belt warning
Optical and acoustic signals
- delayed belt fastened operation
Terminal 15
belt fastened
v > 10 km/h
belt not fastened
Fasten seat belt
Warning lamp for
belt warning
Acoustic signal
t
326_029
Optical and acoustic signals
- belt not fastened operation
Terminal 15
v > 10 km/h
Fasten seat belt
Warning lamp for
belt warning
at least 90 sec
Acoustic signal
t
The warning is reactivated if the belt status is changed
during ”Tm. 15 on”.
26
326_030
Airbag
Driver airbag N95 and N250
A two-stage gas generator is used as the
driver's airbag.
The radial opening of the airbag and the delayed
ignition of the propelling charges reduce the loads
acting on the driver when the car crashes.
Depending on the seriousness and type of accident,
the time lapse between the two ignitions can be
approx. 5 ms to 50 ms.
The radial opening and stepped actuation of the
front airbag is particularly advantageous when
there is no sufficient clearance between the
steering wheel and the upper part of the body.
In general, both propelling charges are always
ignited. This prevents one propelling charge
remaining active after the airbag has been actuated.
The gas generator in the driver's airbag is bedded
in a rubber ring and swings.
This minimizes any vibrations at the steering wheel,
as the gas generator acts as a vibration damper.
282_070
27
Passenger protection
Front passenger airbag N131 and N132
Like the driver airbag, the passenger airbag also
comes with a two-stage gas generator. In contrast to
the driver's airbag, the gas generator in the front
passenger airbag operates according to the hybrid
gas technique. The gas generator comprises two
pyrotechnical propelling charges and a compressed
gas bottle. The airbag control unit ignites the first
propelling charge. The pressure which is produced
accelerates a piston, which opens the gas cylinder.
The escaping gas inflates and fills the airbag. The
ignition of the second propelling charge supplies
the airbag with an additional volume of gas.
Igniter I, N131
Propelling charge I
Piston
Sealing membrane
Propelling charge II
Gas cylinder
Gas:
Argon approx. 94 %
Helium approx. 6 %
Pressure: approx. 220 bar
Gas ducts to airbag
326_004
Igniter II, N132
28
Propelling charge I is ignited
326_021
Propelling charge I burns off
Piston opens the gas cylinder
Gas mixes
Gas fills the airbag
326_022
Propelling charge II is ignited and burns off
326_023
29
Passenger protection
Side airbags N199 and N200
The side airbags have the same design and function
as those fitted in other Audi models. However, they
have been adapted to the new Audi A6‘05.
Vehicles for the North American market are
equipped with side airbags (front), which
are adapted to meet the specific market
requirements.
326_039
Side airbag RDW
326_040
Side airbag NAR
Head airbags N251 and N252
Sideguards
The policy for the sideguard, like all Audi vehicles, is
to cover the entire side window area. New head
airbags are used in the Audi A6´05. The hybrid gas
generator is no longer fitted in the proximity
C-pillar, but in the upper area of the B-pillar. The
centric location of the gas generator ensures an
even filling of the airbag. In addition, the
so-called gas lance is no longer required. As a
result, not only has the total weight been reduced
by approx. 50 per cent, but installation space has
also been created for adjacent components.
Gas generator
326_017
30
Key switch for
disabling airbag,
front passenger side E224
A key switch as shown in the adjacent block
diagram is used to deactivate the front passenger
airbag. Deactivation of the front passenger airbag
is indicated by the airbag warning lamp, front
passenger side, off (K145)
(PASSENGER AIRBAG OFF) lighting up.
The layout of the four resistors, of which two are
always connected in series, ensures correct
detection of the switch position.
R3
R1
R4
R2
326_001
If a faulty key switch is detected by the Diagnosis,
an entry is made in the fault memory. This is also
indicated by a flashing airbag, front passenger side,
off warning lamp.
Seat belts and belt tensioners
N153 and N154
The proven compact tensioners are used for the
front seats in the Audi A6.
The electrically triggered tensioner units operate
according to the ”ball and gearwheel” principle.
The belt tensioner units are triggered before the
front airbags.
To prevent passengers from being subjected to
excessive loads, the automatic belt systems are
equipped with a belt force limiter.
At a certain load level, the force limiter gives and
makes the belt longer, thus permitting the
passenger to sink into the airbag, which has
already opened.
In the event of a side crash with side airbag
actuation, the corresponding belt tensioner is
also triggered.
31
Passenger protection
Belt switches E24 and E25
(in the belt locks)
A belt lock interrogation procedure is planned for
the driver / front passenger belt lock. The switch
position can be determined by means of a
resistance measurement. The measured resistance
value tells the airbag control unit whether the safety
belt has been fastened.
326_049
Belt switch, belt not fastened
Belt switch, belt fastened
Belt switch
Belt switch
326_057
32
326_054
Active headrests
Active headrests are used on the front seats in the
Audi A6’05.
With this system, the headrests move forward in the
event of a rear-impact collision in order to reduce
the distance between the head and the headrest.
Reducing the relative acceleration between
shoulder and head significantly reduces the risk of
whiplash injuries.
A blocking of the mechanics in the event of a frontal
impact, as in the case of the Audi A8‘03, is not
necessary, due to the lower mass of the head
restraints.
Functional unit
”Active head restraint”
Lumbar support
plate
During a rear-impact collision, the passenger is
pressed against the backrest. This force is
transferred via the backrest padding to the lumbar
support plate in the backrest.
The lumbar support plate is linked to the ”Active
headrest” function unit in the backrest head via a
lever mechanism. If the lumbar support plate moves
backwards, the head restraint automatically moves
forwards.
326_024
Functional unit
”Active head restraint”
Lever mechanism
Lumbar support plate
Idle position
326_012
Activated
326_013
33
Passenger protection
Battery cut-off relay J655
The Audi A6‘05, like the Audi A8‘03, will also be
equipped with the battery cut-off function in the
event of a crash.
The battery cut-off relay disconnects the starter and
generator lines from the vehicle's battery (located in
the boot) in the event of a crash. This avoids
short-circuits, which could result in the vehicle
catching fire.
On being triggered by the airbag control unit,
a white field is visible in the element viewing
window instead of a copper coil.
The airbag control unit monitors the diagnosis
process and stores faults which have occurred.
The battery cut-off relay is activated every time an
airbag is triggered and upon detection of a rear-end
crash.
A battery cut-off relay which has triggered must
always be replaced.
The electric battery cut-off relay will be replaced by
a pyrotechnic one in the middle of 2004.
34
326_010
30
15
5 4
3 1
A
+
J655
-
B
2
31
326_018
Pin
Terminal
Input / output
Description
A
30
input
(screw-type terminal)
Battery +
B
87
output
(screw-type terminal)
Output and starter
1
15
input
(clamp-type terminal)
Switched +
2
31
input
(clamp-type terminal)
Chassis ground
3
Crash signal
input
(clamp-type terminal)
Activation from
airbag control unit J234
4
Diagnosis
Input and output
(clamp-type terminal)
Diagnosis line from
airbag control unit J234
5
30
output
(screw-type terminal)
Output to power
management control unit
J644
35
Passenger protection
Seat occupied recognition,
not for USA
Seat cushions
Seat occupied sensor, front passenger side, G128 is
a plastic foil, which covers the rear part of the front
passenger seat. It consists of several individual
pressure sensors. This ensures that the relevant
part of the seat is sensed.
The seat occupied sensor, front passenger side,
reacts to pressure and changes its resistance,
depending on the load. If seat occupied sensor,
front passenger side, G128 is subjected to a load
greater than approx. 5 kg, the airbag control unit
detects ”Seat occupied”. As long as the front
passenger seat is unoccupied, the seat occupied
sensor has a high resistance. If the seat is occupied,
the resistance drops. If the resistance exceeds
480 ohms, the airbag control unit detects an
interruption and sets a fault in the fault memory.
The airbag control unit uses the information from
the seat occupied sensor and the belt lock switch
for the wearing belt detector.
Sensor
326_035
36
Resistance of G128
Evaluation
Approx. 430 - 480 ohm
Seat not occupied
At 120 ohms and less
Seat occupied
Above 480 ohm
Error, interruption
Seat occupied recognition for
US American market
A separate system was developed in order to meet
the legal requirements in this country. The system is
responsible for deactivating the passenger’s front
airbag in certain circumstances.
If the front passenger seat is unoccupied or if a
child seat is detected, the front passenger airbag is
switched off by the airbag control unit.
A deactivated front passenger airbag is indicated by
the PASSENGER AIRBAG OFF warning lamp and a
corresponding message in the dash panel insert.
This type of seat occupied recognition in the
Audi A4 will now be used for the USA (new).
The system comprises the following components:
– Seat cushions
– Mat for seat occupancy detection
– Pressure sensor for seat occupied
recognition G452
– Seat occupied recognition control unit J706
– Wearing belt recognition switch E25
– Seat belt force sensor for seat occupied
recognition G453
– Warning lamp for airbag, front passenger side,
off, K145 (PASSENGER AIRBAG OFF)
– Airbag control unit J234
Warning lamp for airbag,
front passenger side, off
Seat cushions
Switch for wearing
belt recognition
Airbag control unit
Seat belt force sensor
for seat occupied
Mat for seat occupied
recognition
Pressure sensor for
seat occupied recognition
Plug-in connection
under the seat
Isolating point
326_019
37
Passenger protection
Pressure sensor for seat occupied
recognition G452
Pressure sensor for seat occupied recognition G452
is connected to the mat for seat occupied
recognition by means of a hose. The mat, which is
filled with a silicone-like gel is fitted below the seat
cushion. If the front passenger seat is occupied,
pressure is applied to this mat via the seat cushion.
Pressure sensor for seat occupied recognition G452
generates an analogue voltage signal based on this
pressure. The seat occupied recognition control unit
supplies the pressure sensor with a voltage of
5 volts. The signal generated by the pressure sensor
lies between approx. 0.2 and 4.3 volts, depending on
the load on the seat. The higher the load, the lower
the voltage.
Seat belt force sensor for seat occupied
recognition G453
The sensor element is located between the belt lock
and the belt lock fastener, which is fixed to the seat
frame. It consists of two movable parts. Both parts
are held in their idle position by a defined spring.
The seat belt force sensor operates by means of a
hall sensor. On fitting the safety belt correctly, a
tensile force is applied to the belt lock. The sensor
measures the displacement distance of the parts to
each other. The greater the tensile force, the greater
the distance the parts are displaced. This changes
the signal from the sensor. This information is
evaluated by the seat occupied recognition control
unit under the seat. A mechanical stop ensures that
the sensor element is not torn apart in the event
of a crash.
Pressure sensor for
seat occupied recognition
Gel-filled mat for
seat occupied recognition
Protective foil
326_014
Seat belt force sensor, unloaded
326_052
Seat belt force sensor, under load
326_051
38
Wearing belt recognition switch E24
and E25
The wearing belt recognition switch is fitted directly
in the belt lock. Two resistors are integrated within
the switch. The measurement is effected via one or
both of the resistors, depending on the switch
position. The airbag control unit recognizes that the
safety belt has been put on by means of the
measured resistance.
R2
R1
326_020
Switch for wearing belt recognition, belt not fastened
Switch for wearing belt recognition, belt fastened
326_053
326_050
39
Passenger protection
Seat occupied recognition
control unit J706
The control unit evaluates the signals coming from
the pressure sensor and the belt force sensor. The
seat occupied recognition control unit uses the
information it receives from the seat belt force
sensor to monitor the tensile force acting on the
safety belt. The voltage signal from the pressure
sensor can be used to specify the weight of the load
on the front passenger seat.
If the load is under approx. 20 kg, and a very small
or no belt force is discernible, the control unit
recognizes ”child seat” and informs the airbag
control unit. The front passenger airbag is disabled.
If the load on the seat is approx. 25 kg, for example,
and the belt force exceeds a fixed value, the control
unit recognizes that the safety belt is also pressing
the child seat against the seat cushion. The control
unit recognizes ”child seat” and the airbag control
unit disables the front passenger airbag.
From a load of approx. 25 kg and and a low belt
force, the control unit assumes that the seat is
occupied by an adult and the front passenger airbag
remains active.
40
The data from the sensors is continuously evaluated
when the ignition is switched on. This ensures that
the control unit recognizes any seat occupancy
changes and reacts accordingly.
When the vehicle is moving, the system no longer
reacts spontaneously and only does so after a
certain delay. This ensures that the front passenger
airbag is not immediately deactivated when there is
a load change on the seat whilst driving. The
acceleration sensor in the control unit informs the
electronics that the vehicle is moving.
Seat load
Belt force
Recognition
less than approx. 20 kg
very small / none
Child seat
e. g. 25 kg
very high
Child seat
greater than approx.
25 kg
low
Adult
Data exchange between the seat occupied
recognition control unit and other vehicle systems
is effected via the airbag control unit (by means of
the LIN bus). The airbag control unit is thus the
master control unit and the seat occupied
recognition control unit (J706) the slave. The
Diagnosis function is effected via the airbag
control unit.
The positions of the installed components are fixed
and must never be changed.
This also applies to individual system components.
The system, comprising control unit, pressure
sensor, pressure mat and seat cushion, is calibrated
individually for each seat during production.
The connecting cable beween the control unit and
pressure sensor is thus sealed at both ends in order
to emphasize that they are not to be disconnected.
Likewise, the pressure mat is connected to the foam
by means of a clip, which cannot be removed
without distroying it.
All parts must be replaced together in the event of a
defective component. Pre-calibrated Service kits are
available for this.
Components which are not installed correctly
can cause malfunctions and the entire seat
occupied recognition system can no longer operate
reliably.
Characteristic maps in the control unit electronics
ensure that the ageing of individual components is
taken into account.
41
Diagnosis
Diagnosis
As in the case of the Audi A8´03 and Audi A3´04,
communication in the Audi A6´05 between
the VAS tester and the vehicle is effected via
CAN-Bus, CAN-Diagnosis.
The main Diagnosis modification is the Diagnosis
tester online connection.
An adaptation of components belonging to the
immobilizer or interrogation of the radio code, is
only possible when the tester is directly connected
to the company's ”FAZIT” database.
Secret numbers are thus no longer disclosed.
294_001
Reference
For further information on the topic:
VAS 5051 online connection; please refer to
self-study programme 294.
VAS 5053
The VAS 5053 tester was developed for vehicle
acceptance and service procedures and for smaller
repairs.
In addition to the ”Self-diagnosis” function,
excerpts from the ELSA and the ”Guided functions”
programme will be available on the tester.
Due to its compactness, the VAS 5053 is suitable for
portable use, e.g. test drives. The data gathered
during a test drive can be stored in the tester
until it is printed out. The connection between the
vehicle and VAS 5053 tester is established by means
of a cable. In addition, the tester can be connected
to the vehicle via the separate VAS 5053/20 wireless
interface.
On-board vehicle diagnosis
Read fault memory
01 - Engine electronics
8D0907558F
1.8L R4/5V MOTR HS D02
Coding 4001
Workshop code 19480
2 fault detected
16519
P0135
Bank1-Probe1, heating circuit
Electrical fault
16518
P0134
Bank1-Probe1
No activity
Sprung
Drucken
Hilf
e
VAS
5053
326_031
42
VAS 5051
The VAS 5051 A tester will be replaced by the
VAS 5051 B in 2004. The hardware and design of the
VAS 5051 have been revised and updated.
The 15" screen is the most noticeable feature of
the VAS 5051 B.
The main objective of the revision was being able
to use it on the existing instrument waggon and
with the existing test cables.
M esst
echnik
DSO
0.5V/O iv.=
N orm alBetrieb
Trigger feh
lt!
Standbild
1m s/O iv.=
KanalA
KanalB
0
Trigger-M ode
M ess-M ode
0
0.5V/O iv.=
0.00
Position
Dokum ent
Geführte
Fehlersuche
M essung
voreingestell
t
D rucken
M ulti
m eter
H ilfe
326_032
Messtechnik
DSO
0.5V/Oiv.=
Normal Betrieb
Trigger fehlt !
Standbild
1ms/Oiv.=
Kanal A
Kanal B
0
Trigger-Mode
Mess-Mode
0
0.5V/Oiv.=
0.00
Position
Dokument
Geführte
Fehlersuche
Messung
voreingestellt
Drucken
Multimeter
Hilfe
326_033
43
Diagnosis
VAS 5053/20
The VAS 5053/20 wireless Diagnosis interface
permits wireless communication between the
Diagnosis socket in the vehicle and the VAS 5051 B,
VAS 5052 and VAS 5053 Diagnosis testers.
VAS 50
52 / 20
Messtechnik
DSO
0.5V/Oiv.=
Normal Betrieb
Trigger fehlt !
Standbild
1ms/Oiv.=
Kanal A
Kanal B
0
Trigger-Mode
Mess-Mode
0
0.5V/Oiv.=
0.00
Position
Dokument
Geführte
Fehlersuche
Messung
voreingestellt
Drucken
Hilfe
Multimeter
Sprung
Drucken
Hilfe
VAS 5053
326_034
44
Recording the working time
using the VAS 5051/5052
From the basic CD 6.0 onwards, the actual working
time in the ”Guided fault finding” and ”Guided
functions” functions is logged by the tester
and indicated in time units under ”Diagnosis time”
in the Diagnosis log print-out. The time required to
uncover or remove and install components in the
scope of the guided fault finding process is not
recorded by the tester.
Workshop code:
02211 123 12312
Version:
Basic V06.02.00 19/06/2003
Audi V06.50.00 07/08/2003
Company code:
VK-31
Registration no.:
AB-CD 1234
Vehicle Ident. No.:
WAUZZZ.............
Vehicle:
Make:
Type:
Model year:
Variant:
Engine identifier:
Diagnosis time:
Fault memory contents:
Audi
Audi A6 1998>
2000 (Y)
Allroad
AKE 2.5l TDI / 132 kW
36
Motronic ME7 injection and ignition system
4Z7907401
2.5l/4VTEDC G200SG I02
Coding 1018
Company number 02325
1 fault detected
00575 008
Intake manifold pressure
Control limit exceeded
45
Engine / Gearbox
Overview of available engine / gearbox combinations
V6 3.0l TDI
V6 3.2l FSI
V8 4.2l
2.4l
46
Reference:
For information on the engines and gearboxes,
refer to SSP 325
0A3/450Nm
09L/to 450Nm
01J/330Nm
01X/02Xqu
330Nm
09L/to 450Nm
01J/330Nm
01X/02Xqu
330Nm
47
Chassis
Overview
The basic version of the Audi A6´05 is equipped
with a steel spring chassis. There are three different
types of running gear:
Normal chassis:
Sports-style
running gear:
Designation 1BA
Designation: 1BE, vehicle trim is
positioned 20 mm lower than on
the normal running gear
Bad road chassis: Designation 1BR, vehicle trim
position raised by 13 mm
compared to the normal chassis
Front axle
The well-known four-link front axle also used in the
new Audi A6‘05.
Due to the geometric and kinematic modifications
compared to the predecessor, all axle components,
with the exception of the upper axle links and the
wheel hubs (adopted from Audi A8), are new parts.
In addition to improved spring and shock absorber
settings, spring travel has been increased by
30 mm. This results in a significant improvement in
driving comfort and driving stability. With regard to
the passenger compartment, the axle was moved
forward by 83 mm. This provides better axle load
distribution and has advantages from the point of
view of driving dynamics.
Mounting block
Spring/shock absorber unit
Guide arm
Upper axle control arm
Pivot bracket
Stabiliser
Subframe
Supporting arm
48
Wheel bearing/
Wheel hub
323_050
Rear axle
The rear axle represents a further development of
the trapezoid link axle, with which you may be
familiar from the A4’00. Because of the geometric
and kinematic changes compared with the
predecessor vehicle and the use of the trapezoid
link axle, all axle components are new parts.
The axle struts are now longer compared with
the A4`00 in order to guarantee a larger toe width.
For vehicles with the V8 TDI engine with quattro
drive, the rear axle track width will be reduced in
order to fit wider tires. This will be realised by using
modified wheel hubs and a greater wheel offset.
Wheel carrier
Subframe
Shock
absorber
Transverse
control arm
Spring
Trapezoidal control arm
Wheel bearing
323_051
49
Chassis
Wheel brake
Front-axle overview
Engine
3.0 litre V6 TDI
3.2 litre V6 FSI
4.2 litre V8 MPI
Minimum wheel size
16”
16”
17”
Brake type
FNR-G 60 16”
FNR-G 60 16”
FNR-G 60 17”
Number of pistons
2
2
2
Piston diameter (mm)
60
60
60
Brake disc diameter (mm) x
thickness (mm)
321 x 30
Ventilated
321 x 30
Ventilated
347 x 30
Ventilated
Engine
3.0 litre V6 TDI
3.2 litre V6 FSI
4.2 litre V8 MPI
Minimum wheel size
16”
16”
17”
Brake type
Colette II C41
Colette II C41
Colette II C43
Number of pistons
1
1
1
Piston diameter (mm)
41
41
43
Brake disc diameter (mm) x
thickness (mm)
302 x 12
Not ventilated
302 x 12
Not ventilated
330 x 22
Not ventilated
Rear-axle overview
50
ESP
A new ESP generation from Bosch in the form of
ESP 8.0 is used in the Audi A6'05. The familiar basic
functions already available in the other Audi models
have been adapted to the conditions in the A6´05.
The basic functionalities of the subfunctions EBD,
ABS, TCS, EDTC, EDL, ESP and ECD are the same as
in the predecessor version 5.7. The control unit
and hydraulic unit cannot be separated in
Customer Service. There are two different parts
for front-wheel-drive and quattro drive.
Pump motor
Pilot valves
Valve block
Pressure sensor
Control unit
323_052
Electromechanical parking brake – EPB
Following its initial introduction in the Audi A8, the
electromechanical parking brake EPB is now also
used in the Audi A6´05. The basic mechanical
design, the boost factor levels and the general
functionality are still the same (see SSP 285). The
innovations described in SSP 324 are due to its
adaptation to the A6´05.
323_053
51
Chassis
Steering system
A mechanically adjustable steering column is
used in the basic model. Electrical adjustment is
optional.
As in the case of the A8´03, the A6´05 also has an
electrical steering lock.
A newly developed three/four-spoke steering-wheel
generation is used.
A conventional, hydraulic rack-and-pinion servo
steering system is used.
A high degree of sporty steering precision
has been achieved through the consistent further
development of the steering used in the
predecessor model. The speed-dependent
Servotronic servo-support is available as standard.
Servotronic II, which was already used in the
Audi A8, is used (set-up and mode of operation:
see SSP 285).
Steering gear
Oil reservoir
Suction hose
Steering pump
Expansion hose
Return hose
Return line
Servo oil cooler
323_054
52
Wheels / tyres
Engine
4 and 6-cylinder
8-cylinder
Basic wheels
Winter wheels
Optional wheels
7J x 16 ET 35 (1)
Cast alum. wheel
205/60 R16
7J x 16 ET 42 (4)
Forged alum. wheel
205/60 R16 or
225/55 R16
7.5J x 16 ET 45 (7)
Cast alum. wheel
225/55 R16
8J x 17 ET 48 (10)
Cast alum. wheel
245/45 R17
7.5J x 16 ET 45 (2)
Forged alum. wheel
225/55 R16
225 x 460 ET 46 (5)
Cast alum. wh. (PAX)
225/650 – 460
7.5J x 17 ET 45 (8)
Cast alum. wheel
225/50 R17
8J x 18 ET 48 (11)
Cast alum. wheel
245/40 R18
7.5J x 17 ET 45 (3)
Cast alum. wheel
225/50 R17
7J x 17 ET 42 (6)
Cast alum. wheel
225/50 R17 98 M+S
7.5J x 17 ET 45 (9)
Cast alum. wheel
225/50 R17
8J x 18 ET 48 (12)
Forged alum. wheel
245/40 R18
Run flat system PAX
225 x 460 ET 46 (13)
Cast alum. wh. (PAX)
235/660 – R460
323_055
Tyre pressure monitoring
system
A new generation of the tyre pressure monitoring
system is available for the Audi A6´05.
It is modular in design and is significantly different
from the systems used up to now at Audi from the
point of view of functionality and design.
53
Electrics
Bus topology
Distance control
J428
Control unit in
dash panel insert
J285
Diagnosis interface
for data bus
J533
Data link connector
T16
NOX sensor
J583
Engine electronics 1
J623
Door control unit,
driver’s side
J386
Power
management
J644
Rotation rate sensor
G202
ABS with EDL
J104
Door control unit,
passenger’s side
J387
Auxiliary heating
J364
Seat occupied
recognition
J706
Airbag
J234
Door control unit,
rear left
J388
Parking aid
J446
Automatic
transmission
J217
Door control unit,
rear right
J389
On-board power
supply 2
J520
Headlight range
control
J431
Seat adjustment with
memory, steering
column adjustment
J136
Access and
start authorisation
J518
Electric parking /
handbrake
J540
Seat adjustment with
memory, pass. side
J521
On-board power
supply
J519
Level control
J197
Trailer detection
J345
Central contr. unit for
convenience system
J393
Power module
for left headlight
J667
Power module
for right headlight
J668
Sender for
sensor
G85
Steering column
electronics
J527
Multi-function
steering wheel
J453
54
Climatronic
J255
Tyre pressure
monitoring
J502
Transmitter and
transmitter and
for telephone
R36
Handset
for telephone
R37
Telephone/telematics
J526
Display and
operating unit for
front information
J523
Navigation
with CD drive
J401
TV tuner
R78
CD changer
R41
Digital
sound package
J525
Radio module
R
Voice input
J507
MOST bus
CAN Instrument cluster
Switch for
access and
start authorisation
E415
Antenna read-in
unit for keyless access
authorisation
J723
CAN Diagnosis
CAN Drive
Wiper motor
J400
CAN Convenience
Sensor for rain and
light detection
G397
CAN Distance control
LIN bus
Passenger
compartment
monitoring
G273
Fresh air fan
J126
Transmitter,
front left
G431
Alarm horn
H12
Various sub-bus systems
Wireless transmission
- Bluetooth signal
Refrigerant pressure and
refrigerant temperature
G395
Transmitter,
front right
G432
Transmitter,
rear left
G433
Transmitter,
rear right
G434
Antenna, rear
R96
326_027
55
Electrics
In/outputs on control units J393, J519 and J520
This overview shows all load modules in the
convenience system with their in/outputs.
You thus have all 3 control units and their basic
functions at a glance. For further details, please
refer to the function plans in self-study
programme 326 A6´05, Electrics.
This overview only contains discretionary wired
components. Components which communicate
with the control units via various bus systems
are shown in the vehicle topology.
E1 Light switch
E3 Hazard warning light switch
F4 Switch for reversing lights
F266 Contact switch for bonnet
G357 Sender for vertical steering column adjustment
G358 Sender for axial steering column adjustment
J519 Onboard power supply control unit
Master functions:
– Exterior lights
– Wiper and washer
CAN Convenience
Inputs (source)
Outputs (receiver)
J4 Relay for dual-pitch horn
J39 Relay for headlight cleaning system
K4 Indicator light for parking light
K6 Indicator light for hazard warning lights
E13 Indicator light for rear fog light
E17 Indicator light for fog lights
L13 Gas discharge light, left
L14 Gas discharge light, right
L22 Lamp for left fog light
L23 Lamp for right fog light
L174 Lamp for daytime driving light, left
L175 Lamp for daytime driving light, right
M1 Lamp for parking light, left
M3 Lamp for parking light, right
M5 Lamp for direction indicator light, front left
M7 Lamp for direction indicator light, front right
M18 Lamp for side direction indicator light, left
M19 Lamp for side direction indicator light, right
N395 Magnet for cover adjustment, left headlight
N395 Magnet for cover adjustment, right headlight
V5 Windscreen washer pump
V123 Motor for vertical steering column adjustment
V124 Motor for axial steering column adjustment
W9 Footwell light, left
W10 Footwell light, right
F218 Switch for tailgate central locking
F248 Button for unlocking tailgate lock cylinder
530 Control unit for opening garage door (adaptation flashing)
F124 Contact holder in lock cylinder for tailgate
F334 Switch for tank cap detection (USA only)
J234 Airbag (crash signal)
Terminal 15
F Brake light switch
J104 Control unit for ABS with EDL (ECD brake)
56
E316 Glove compartment button
J520 Control unit 2 for on-board power supply
N119 Solenoid valve for Servotronic
V1 Motor for sliding roof:
– Speed signal
– Convenience opening
– Convenience closing
V327 Motor for glove compartment release
J393 Central control unit for convenience system
Master functions:
– Flashing
– Central locking
– Interior light
– Anti-theft warning system
J9 Relay for rear window heater
L106 Lighting for footwell, rear left
L107 Lighting for footwell, rear right
M2 Lamp for tail light, right
M4 Lamp for tail light, left
M6 Lamp for direction indicator light, rear left
M8 Lamp for direction indicator light, rear right
M9 Lamp for left brake light
M10 Lamp for right brake light
M16 Lamp for reversing light, left
M17 Lamp for reversing light, right
M25 Lamp for high-level brake light
M49 Lamp for tail light 2, left
M50 Lamp for tail light 2, right
M54 Lamp for tail light 3, right
M55 Lamp for tail light 3, left
V1 Motor for sliding roof (release)
V53 Motor for tailgate central locking
V91 Motor for rear sun blind
V155 Motor for tank cap locking
W3 Boot light
W35 Boot light, right
X Number plate lights
Terminal 30 for interior light (switched)
Door contact signal, interior light (dimming ground-controlled)
Door contact signal for engine control unit (FSI only)
Door contact signal for air suspension
323_018
57
Air conditioning
Overview
The new Audi A6´05 is equipped with an air
conditioning system as standard. A differentiation
is made between automatic air conditioning and
convenience automatic air conditioning plus. The
main characteristics of the air conditioning system
in the new A6´05 are the low interior noise level,
no-draught ventilation and even temperature
distribution.
During the development process, particular
attention was paid to weight and space-saving
but output-optimized) components.
323_012
Air conditioning unit for Audi A6´98
The familiar air conditioning concept used in the
AUDI A6 predecessor has been replaced by a
symmetric concept, in which the fresh air blower is
located outside the passenger compartment. The
previous air-based air conditioning control system
has been converted to a water-based control system
with valves for heating control left and right (N175/
176 ) and a pump for coolant circulation (V50) like in
the current Audi A8.
The new concept is more or less the same for both
the left-hand and right-hand drive variants. This
reduces the number of variants.
Reference
For information on the 6-piston swash-plate
compressor, please refer to SSP 240,
Audi A2 – Technology.
58
Audi A6´05 air conditioning unit
The new Audi A6´05 – like the Audi A2 and
Audi A3´04 – will be equipped with the familiar
6-piston swash-plate compressor with control
valve N280 and out-flow temperature sender for
evaporator G263. The compressor has the same
working volume of 140 cm3 for all country variants.
In the case of the 4 and 6-cylinder engines, it is
driven via a plastic belt pulley and in the case of
the 8-cylinder engine, via a shaft.
323_011
323_013
59
Air conditioning
Convenience automatic air conditioning and convenience
automatic air conditioning plus
The new Audi A6´05 will still use an automatic air
conditioning system with two-zone temperature
control as standard equipment. Both the basic and
convenience versions now have a circulating air
filtering system (extended function) in which the
filter element has been integrated within the
distributor housing. Both versions have a central
nozzle with adjustable temperature in the dash
panel insert.
The control for the optional seat heating and
ventilation is integrated within both variants of
Climatronic control unit J255.
Both versions of the automatic air conditioning
system use the respective display on the multimedia interface as the display unit. They are still
operated at the separate Climatronic control
unit J255).
323_014
The automatic air conditioning plus system also
has two additional displays in Climatronic control
unit J255. Furthermore, it also has an indirect
ventilation in the dashboard.
In addition, an air quality sensor for automatic fresh
air / circulating air changeover is installed. The
residual heat function makes it possible to use the
engine heat when the vehicle is stationary.
323_015
60
Convenience automatic
air conditioning
Convenience automatic
air conditioning Plus
A6
Predecessor
Separate temperature distibution
X
X
X
Sun position sensor
X
X
X
Air quality sensor
-
X
X
Residual heat
-
X
-
Pollen filter / combination filter
X/-
-/X
-/X
Circulating air filter
X
X
-
Indirect ventilation
-
X
-
Rear compart. ventilation (middle)
X
X
X
Rear compartment ventilation (B-pillar)
-
X
-
Central air vent with adjustable temperature
-
X
-
Control concept
water-based
water-based
air-based
CAN networking
The air conditioning system in the new Audi A6´05 is
integrated within the convenience CAN (see table).
In addition to the air conditioning master control,
Climatronic control unit J255 is the master control
unit for the distributed functions rear window
heating, the optional seat heating and the optional,
factory-fitted auxiliary heater.
Most of the necessary data messages are
transmitted to Climatronic control unit J255 by
means of the CAN bus. The unit also transmits
messages via this data bus, which are used for the
distributed functions at the other control units.
This data bus is also used for the analysis of the air
conditioning system in the event of malfunctions, in
conjunction with Diagnosis interface for data
bus J533, CAN-Diagnosis and the corresponding
Diagnosis tester.
The personalization of the air conditioning settings
is effected by importing the respective code
identification message from the control unit for
access and start authorization J518. Fresh air
blower control unit V2 is connected to Climatronic
control unit J255 via a LIN bus. The control unit for
solar operation (J355) of the optional solar sliding
roof is connected directly to Fresh air blower
control unit V2. Communication with Climatronic
control unit J255 is effected via Fresh air blower
control unit V2, which sends a LIN message to
Climatronic control unit J255 when it receives
voltage signals from the control unit for solar
operation (J355). This message is then forwarded to
the control unit for convenience electronics (J393),
which needs this information for the interior
monitoring function.
61
Air conditioning
The rear window heating is activated from
Climatronic control unit J255. A message is sent
to convenience system control unit J393 via
CAN-Convenience. This actuates heated rear
window Z1 and sends a CAN bus message to
Climatronic control unit J255 that it has been
switched on. The control unit then activates the
respective LED in the button.
The air conditioning system (both variants) in the
new Audi A6´05 uses the MMI display to display
relevant information. The current MMI display
switches over to the air conditioning menu on
pressing the function switch on Climatronic control
unit J255.
MOST bus
CAN Instrument Cluster
Display unit in dash panel insert J285
CAN Diagnosis
CAN Drive
CAN Convenience
LIN bus
Various sub-bus systems
Diagnosis connection T16
Aux. heating
element
Z35
Engine
electronics 1
J623
Access and start
authorisation
J518
Aux. heating
J364
Heated
rear window
Z1
62
Convenience
system
J393
On actuating an air conditioning function, the
MMI display switches back to its original menu
after a certain waiting time.
The information required for this is sent
from Climatronic control unit J255 to the
CAN-Convenience, converted into messages for
the MOST bus by Diagnosis interface for data
bus J533 and fowarded as optical signals to front
display and operating unit control unit J523.
This in turn converts the incoming signals into data
to be displayed on the respective display (J685)
which is connected.
Display unit for front
information display
and operating unit
control unit
J685
Display and
operating unit for
information, front,
J523
Diagnosis interface
for data bus
J533
Power
management
J644
On-board power
supply
J519
Climatronic
J255
Fresh air
blower
J126
Sender for
refrig. pressure
G395
323_016
63
Air conditioning
Components in the Audi A6´05 air conditioning unit
Control motors
Driver’s side
Front left chest vent
control motor, V237
Control motor for indirect
ventilation flap, V213
Control motor for central vent, V102
Left footwell flap control motor, V107
323_020
64
Passenger’s side
Control motor for cold air flap V197
Front right chest vent control
motor, V238
Right footwell flap control motor, V108
Control motor for defrost flap V205
Control motor for passenger compartment vent, V112
323_019
65
Air conditioning
Replacing components
The air conditioning unit in the new Audi A6´05 does
not have to be completely removed from the vehicle
to replace components. Functional units such as the
evaporator or control motors, for example, are
replaced in the vehicle. The evaporator, for example,
will be available as a separate spare part in the
scope of the Customer Service process.
The evaporator is replaced by splitting the air
conditioning unit housing at the groove and pulling
the evaporator out sideways.
After fitting the new evaporator, the air conditioning
unit housing is closed by means of a service flap
prepared for Customer Service procedures. This
must be ordered as a separate spare part and is
fixed to the air conditioning unit housing by means
screws.
Service flap for replacing the evaporator
Cut-out for replacing the evaporator
Service flap
323_021
66
Changing the pollen filter
The pollen filter, which has to be changed regularly
in accordance with the service specifications, is
accessible from the passenger footwell. It is divided
into two parts horizontally. After the bottom half
has been pulled out sideways from the air
conditioning units housing, the top half must first
be pulled downwards and then also be pulled out
sideways.
In order to ensure a thorough cleaning of the
installation position of the pollen filter during the
filter change, a suction nozzle was developed with
which the installation shaft in the air conditioning
unit can be cleaned before the new filter is fitted.
323_022
Using the special tool ”Suction nozzle T40073” to change the pollen filter in the vehicle
323_029
Two-part pollen filter in the new Audi A6´05
67
Air conditioning
Control motor versions
The redesigned air conditioning unit in the
Audi A6´05 uses modified kinematics for the
individual control motors.
Always note the exact part numbers when changing
control motors. Otherwise, control motors which
have the same housing, but different functions
might be placed in the wrong position. As a result,
the basic setting of the air conditioning system
would not be possible. Attention must also be paid
to the difference between the convenience
automatic air conditioning and convenience
automatic air conditioning plus versions when
changing control motors.
In the basic version, the control motors for the left
chest vent, V237, are installed in the position of the
right chest control motor, V238, which is then no
longer used. The same is true of the left footwell flap
control motor, V108, which is then in the V109's
position on the right. The reason for this is the
steering rod shaft positioning of flaps in the basic
version, where the respective left flap is controlled
by the one on the right.
Front left chest vent control motor, V237
Left footwell flap
control motor,
V107
Front right chest vent
control motor, V238
Right footwell flap control motor, V108
323_023
Control motors for left and right chest vents, V237 and V238, as well as control motors for left and right
footwell flaps V107 / V108 for flap positioning in the convenience version.
68
In/output signals at Climatronic control unit J255
CAN-Convenience output signals
Information on the status
of the compressor
... displays whether the compressor is switched on or off. Switched on means
that the compressor is within the control range, in other words, a current of
300 – 800 mA is flowing through the compressor.
Speed increase
... is transmitted from the air conditioning system to the motor if the air
conditioning system needs an increased heating or cooling capacity. This
message is not related to the compressor status.
Refrigerant pressure
The air conditioning system reads the pressure sensor and sets the signal to
CAN-Convenience. The determination of the refrigerant pressure occurs every
100 ms.
Radiator fan control
Subject to the required condensor cooling, the air conditioning system issues
a "radiator fan control". This value can lie between 0 and 100 %. This value
depends on the refrigerant pressure and the information on petrol / diesel
engine from the diagnosis interface for data bus J533.
Power reduction of air
conditioner compressor
A reduction of the compressor power is possible by means of the externally
controlled compressor. The aim here is that the engine electronics control
unit J623 uses this infomation and only completely shuts down the
compressor in critical situations.
Compressor torque
transmission
The air conditioning system informs engine electronics control unit J623 of
the torque the compressor takes from the engine. Climatronic control
unit J255 considers the engine and compressor speed transmission ratio of
the various engines. The necessary information on the number of cylinders is
provided by the message from diagnosis interface for data bus J533.
Rear window heating
This message signals to the control unit for on-board power supply J519 that
the rear window heating is to be switched on and this unit then takes over the
power control of the rear window heating.
Left/right sun sensor
The amount of sunlight penetration measured by the sun sensor in W/m²
is supplied by the CAN-Convenience.
Seat heating
This message transmits the different levels of seat heating left or right.
In the versions without seat heating level 0 is always transmitted.
Auxiliary heating
The auxiliary heating can be switched on directly from Climatronic control
unit J255 via the auxiliary heating BIT. Climatronic control unit J255 transfers
the decision on the activation of auxiliary heating or auxiliary ventilation
via the "Auxiliary ventilation indicator light" bit.
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Air conditioning
CAN-Convenience input siganls
Vehicle speed
The vehicle speed is used for the calculation "Setting the air congestion flap".
Engine speed
Start recognition: the program defines
"Engine off", if n < 200 rpm (below starter speed)
"Engine on", if n > 500 rpm is read.
Terminal 58d
Dimming value for the display and function lighting in %.
Terminal 58s
Dimming value for the button lighting in %.
Outside temperature
Climatronic control unit J255 reads the temperature sensor for fresh air intake
duct G89 and puts this unfiltered on the CAN-Convenience. The display unit in
dash panel insert J285 reads temperature sensor G17 installed in the front of
the car and puts the lowest of the two outside temperatures read on the
CAN bus.
Engine temperature
The engine electronics control unit J623 provides this value on the CAN bus.
Key information
The display unit in dash panel insert J285 transmits a key number between "1"
and "4" to Tm. 15. In Climatronic control unit J255, the respective driverspecific settings for each key number are saved and recalled.
The last settings called up either in auxiliary heating mode or for incorrectly
received key numbers are saved in key number "0".
Compressor off
Switches off the compressor from the engine control unit.
Compressor power reduction
Feedback message from engine electronics control unit J623.
Auxiliary heating / auxiliary
ventilation
If a CAN-compatible auxiliary heating is installed, Climatronic control
unit J255 is switched to auxiliary heating or auxiliary ventilation mode.
The decision whether to activate the auxiliary heating or the auxiliary
ventilation is made from Climatronic control unit J255.
Radiator fan control
Actual value of the radiator fan control from engine electronics control
unit J623.
Engine overheating advance
warning
If this message is transmitted on the CAN, the compressor with control
valve N280 must be switched off, regardless of the engine temperature.
Consumer switch-off
Message from control unit for power management J644
Feedback
Rear window heating
Message on the successful activation of the rear window heating from control
unit for convenience system J393.
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Analogue input and output signals
The temperature sensor for fresh air intake duct G89
in the plenum chamber, the middle vent
temperature sensor and the two vent temperature
senders, left G150 and right G151 are read as an
analogue voltage signal at Climatronic control
unit J255.
Furthermore, Climatronic control unit J255 receives
a total of ten feedback reports from the individual
flap positioning motors, the signals from sunlight
penetration photosensor G107, the signal from the
vent temperature sender for evaporator G263, as
well as the signal from the air quality sensor G238.
The compressor with control valve N280 is
controlled via a pulse width-modulated signal.
Additional air heater unit
Depending on the equipment installed, an electric
additional air heater unit is installed in some diesel
versions of the new Audi A6´05. The operating
principle of the additional air heater is, as with the
Audi A6's predecessor, ceramic PTC resistors and
commutators which are heated by an electric
current and which generate this heat to the air
flowing through. The control of the additional air
heater is transferred to the respective engine
electronics control unit J623.
Aux. heating
element
Z35
Engine
electronics 1
J623
If additional heating is required, Climatronic control
unit J255 sends an appropriate message containing
the required output level to CAN-Convenience. This
is converted into a message for the CAN-Drive by
the diagnosis interface for data bus J533 and is
picked up by engine electronics control unit J623.
However, additional heating can only be provided if
the generator's capacity utilization is not too high.
Diagnosis interface
for data bus
J533
Climatronic
J255
323_017
71
Air conditioning
Auxiliary / additional heating
The auxiliary heating which is available ex-works is
installed on the longitudinal member, front right
under the headlight. It is incorporated into the
CAN-Convenience via auxiliary heating control
unit J364 (see topology illustration). Climatronic
control unit J255 is the master control unit for the
auxiliary heating. The interior of the vehicle can be
heated up much more quickly as a result of the
integration of the auxiliary heating into the small
heating circuit. The auxiliary heating can be
programmed and activated via the multi-media
interface, by means of the preselection function.
It can also be activated via the updated remote
control.
Climatronic control unit J255 decides on the
auxiliary heating or auxiliary ventilation mode, the
respective symbol is shown as a function display on
the display unit in dash panel insert J285 after the
respective message is received. The auxiliary
heating basically runs in fresh air mode, whereby
the blower is resticted to 40 %.
Positive feedback, auxiliary heating active
ON
323_024
Negative feedback, auxiliary heating not active
ON
323_025
The new feature here is the bi-directional
communication between the remote control for the
auxiliary heating and the radio receiver for auxiliary
heating R64. The antenna for the radio receiver for
auxiliary heating is installed as a module of the
antenna system in the rear window; the range of the
radio remote control is now up to 600 meters.
72
The user receives feedback on whether the
activation of the auxiliary heating was succesful or
not via a LED which is integrated in the radio remote
control.
Switch-on conditions:
Switch-off conditions:
no tank warning
Auxiliary heating active longer than 60 min
no crash signal from airbag control unit
VAS diagnosis tester function basic setting
no cut-off level from control unit for power management
Heater units error in operational mode
no message "Transport mode active" from control unit for
power management J644
Tank warning during operation
Crash signal during operation (in auxiliary
heating mode)
Cut-off level of control unit for power
management J644
In addition to the auxiliary heating with
CAN networking which is offered ex-works,
a conventional auxiliary heating without
CAN networking can be retrofitted in the customer
service process. To do that, wiring terminal 15,
as well as Climatronic control unit J255,
which has a separate input for this purpose, must be
adjusted accordingly. You can find more detailed
information on this in the respective installation
manual.
Reference
Please refer to the respective operation
manual for instructions on operating the
optional auxiliary heating.
Note
The telestart antenna is fused separately.
Defect fusing results in an appropriate fault
memory entry.
73
Air conditioning
Air conditioning diagnosis
The diagnosis options listed in the table are
available via the diagnosis tester. For this purpose,
the diagnosis on the CAN-Diagnosis and on the
diagnosis interface for data bus J533 is performed
in Climatronic control unit J255.
All input and output signals of Climatronic control
unit J255 can be diagnosed according to the
following error types:
– Line interruption
– Short circuit after positive
– Short circuit after ground
– Block (control motors)
– Plausibility of data bus signals
The actuator test of the air conditioning system is
now sequentially (complete performance of all
actuator tests) and selectively (selection of
individual actuator tests) possible. The following
conditions must be met before the actuator test can
be performed.
– no compressor switch-off condition active
– Vehicle speed < 5 km/h
– 300 / min < engine speed < 3000 / min
Otherwise the message "Function unknown or
cannot be performed at the moment" is displayed in
the diagnosis tester. During the basic setting of the
air conditioning system, all flap positioning motors
are simultaneously moved to their limit positions.
These positions are then saved in Climatronic
control unit J255. During the basic setting, certain
fault memory entries are deleted, with the exception
of those identified during the basic setting. In
addition, the activation of the compressor is only
allowed after the basic setting. Up until then,
Climatronic control unit J255 remains in ECON
mode, which cannot be deactivated. After the
successful basic setting, Climatronic control
unit J255 remains in ECON mode, which can now,
however, be deactivated at any time by means
of the AUTO or ECON button.
Since Climatronic control unit J255 is component
protected, the exchange of the component without
vehicle-specific adaptions can cause restricted
functionality.
In contrast to the current Audi A8 and Audi A3,
during a recoding of a Climatronic control unit J255,
no information on the networking is taken from the
diagnosis interface for data bus or the engine
control unit. In the case of the Audi A6´05, the
coding is performed completely by the entries at the
diagnosis tester.
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Special tools for the Audi A6´05 air conditioning system
Puller T40072
Ratchet spanner T40083
323_027
323_026
Suction nozzle with brush T40073/1 and hose T40073/2
323_028
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323
Vorsprung durch Technik www.audi.co.uk
Service Training
Audi A6´05
Self-Study Programme 323
All rights reserved.
Subject to technical
change.
Copyright
AUDI AG
I/VK-35
Service.training@audi.de
Fax +49-841/89-36367
AUDI AG
D-85045 Ingolstadt
Technical release 01/04
Printed in Germany
A04.5S00.06.20
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