BRAKES—ABS LAMP ILLUMINATED AND DTC Article No. C1235

BRAKES—ABS LAMP ILLUMINATED AND DTC
C1235, C1236, C1237—VEHICLES WITH
DIFFERENTIAL-MOUNTED REAR WHEEL SPEED
SENSOR
Article No.
03-26-3
FORD: 2002-2004 EXPLORER
LINCOLN: 2003-2004 AVIATOR
MERCURY: 2002-2004 MOUNTAINEER
c. Reach up and over the passenger side of
the differential housing to access sensor.
ISSUE
Some vehicles may exhibit an Anti-Lock Brake
System (ABS) warning lamp illuminated with
Diagnostic Trouble Codes (DTCs) C1235, C1236
and/or C1237 (Wheel Speed RR Input Signal
Missing/Wheel Speed LR Input Signal Missing/Rear
Wheel Speed Sensor Output Failure) stored in
memory. This may be due to an intermittently
functioning differential-mounted Rear Wheel Speed
Sensor.
d. Remove the hold-down bolt and remove
sensor from differential housing (3/8″
socket).
e. Unlatch red locking tab on the top of the
electrical connector by sliding it away from
the sensor, then release connector latch and
disconnect connector from sensor.
ACTION
f. Install new sensor and torque hold-down
bolt to 27 N•m (20 lb-ft).
To service, refer to the following diagnostic and
repair procedure.
NOTE
THIS TSB ONLY APPLIES TO VEHICLES WITH
DTCS C1235, C1236 AND/OR C1237. FOR ALL
OTHER DTC’S, REFER TO THE APPROPRIATE
WORKSHOP MANUAL.
NOTE
THIS TSB DOES NOT APPLY TO VEHICLES
EQUIPPED WITH ADVANCETRAC (STABILITY
ASSIST / IVD).
SERVICE PROCEDURE
1.
Retrieve Continuous ABS DTC(s).
2.
If C1235, C1236 and/or C1237 are present,
turn ignition OFF and replace the
differential-mounted Rear Wheel Speed Sensor.
a. Raise vehicle on hoist so that the bottom of
the rear differential is at head level.
b. Stand slightly in front of the rear differential
pinion flange, facing the rear of the vehicle
(Figure 1).
g. Connect the electrical connector to the
sensor.
NOTE
IT IS NO LONGER NECESSARY TO APPLY
F8AZ-19G208-AA GREASE TO THE ELECTRICAL
CONNECTOR AS PREVIOUSLY RECOMMENDED.
3.
Clear Continuous ABS DTC(s).
4.
Verify repair.
NOTE
THE ABS SYSTEM CONFIRMS REAR WHEEL
SPEED SENSOR SIGNAL INPUT BASED ON
SEVERAL WHEEL REVOLUTIONS ABOVE 24
KM/H (15 MPH). DRIVE VEHICLE FOR AT LEAST
75 FEET AT OR ABOVE 15 MPH. IF WHEEL
SPEED SIGNAL INPUT IS MISSING THE ABS
LIGHT WILL ILLUMINATE.
PART NUMBER
4L2Z-9E731-AA
PART NAME
Wheel Speed Sensor
NOTE: The information in Technical Service Bulletins is intended for use by trained, professional technicians with the knowledge, tools, and equipment to do
the job properly and safely. It informs these technicians of conditions that may occur on some vehicles, or provides information that could assist in proper
vehicle service. The procedures should not be performed by “do-it-yourselfers”. Do not assume that a condition described affects your car or truck. Contact a
Ford, Lincoln, or Mercury dealership to determine whether the Bulletin applies to your vehicle. Warranty Policy and Extended Service Plan documentation
determine Warranty and/or Extended Service Plan coverage unless stated otherwise in the TSB article.The information in this Technical Service Bulletin
(TSB) was current at the time of printing. Ford Motor Company reserves the right to supercede this information with updates.The most recent information is
available through Ford Motor Company’s on-line technical resources.
Copyright  2003 Ford Motor Company
PAGE 1
Article No. 03-26-3 Cont’d.
OTHER APPLICABLE ARTICLES: NONE
WARRANTY STATUS: Eligible Under Provisions Of
New Vehicle Limited
Warranty Coverage
OPERATION DESCRIPTION
TIME
032603A
Replace The Differential
0.5 Hr.
Mount Rear Wheel Speed
Sensor (Includes Time To
Check For Codes Replace
Sensor And Clear Codes)
DEALER CODING
CONDITION
BASIC PART NO.
CODE
9E731
42
Figure 1 - Article 03-26-3
PAGE 2