MIL TROUBLESHOOTING. Honda CBR125R

FUEL SYSTEM (PGM-FI)

MIL TROUBLESHOOTING

MIL 1 BLINK (MAP SENSOR)

1. Sensor Unit Power Line Inspection

Check the sensor unit power line inspection

(page 5-16).

Is the sensor unit power line normal?

YES –

GO TO STEP 2.

NO – Replace or repair of the abnormal circuit.

2. MAP Sensor Output Voltage Inspection

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the test harness terminals.

Connection: 27 (+) – 4 (–)

Standard: 2.6 – 3.2 V (20 ° C/68 ° F)

Is the voltage within 2.6 – 3.2 V (20

°

C/68

°

F)?

YES – • Intermittent failure

• Loose or poor contact on the ECM connector

NO –

• About 5 V: GO TO STEP 3.

• About 0 V: GO TO STEP 4.

(4) (27)

3. MAP Sensor Output Line Open Circuit

Inspection 1

Turn the ignition switch OFF.

Disconnect the sensor unit 5P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the sensor unit 5P connector of the wire side.

Connection:

Light green/yellow (+) – Green/orange (–)

Standard: 3.80 – 5.25 V

Is the voltage within 3.80 – 5.25 V?

YES – Faulty sensor unit (MAP sensor)

NO – Open circuit in Light green/yellow wire

4. MAP Sensor Output Line Short Circuit

Inspection

Turn the ignition switch OFF.

Disconnect the sensor unit 5P connector.

Check for continuity between the sensor unit 5P connector terminal of the wire side and ground.

Connection: Light green/yellow – Ground

Is there continuity?

YES – Short circuit in Light green/yellow wire

NO –

GO TO STEP 5.

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminals)

G/O

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

Lg/Y

Lg/Y

5-33

FUEL SYSTEM (PGM-FI)

5. MAP Sensor Output Line Open Circuit

Inspection 2

Check the continuity between the ECM test harness and sensor unit 5P connector of the wire side.

Connection: 27 – Light green/yellow

Is there continuity?

YES – Faulty sensor unit (MAP sensor)

NO – Open circuit in Light green/yellow wire

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

Lg/Y

(27)

MIL 7 BLINKS (ECT SENSOR)

• Before starting the inspection, check for loose or poor contact on the ECT sensor 3P connector and recheck the MIL blinking.

1. ECT Sensor Input Voltage Inspection

Turn the ignition switch OFF.

Disconnect the ECT sensor 3P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the ECT sensor connector of the wire side and ground.

Connection: Yellow/blue (+) – Ground (–)

Standard: 4.75 – 5.25 V

Is the voltage within 4.75 – 5.25 V?

YES –

GO TO STEP 3.

NO –

GO TO STEP 2.

ECT SENSOR 3P CONNECTOR

(Wire side/female terminal)

Y/Bu

2. ECT Sensor Short Circuit Inspection

Turn the ignition switch OFF.

Check for continuity between the ECT sensor connector of the wire side and ground.

Connection: Yellow/blue – Ground

Is there continuity?

YES – Short circuit in Yellow/blue wire

NO –

GO TO STEP 3.

Y/Bu

ECT SENSOR 3P CONNECTOR

(Wire side/female terminal)

5-34

FUEL SYSTEM (PGM-FI)

3. ECT Sensor Resistance Inspection

Turn the ignition switch OFF.

Measure the resistance at the ECT sensor terminals.

Connection: Yellow/blue – Green/orange

Standard: 2.3 – 2.6 k Ω (20 ° C/68 ° F)

Is the resistance within 2.3 – 2.6 k

Ω

(20

°

C/68

°

F)?

YES –

GO TO STEP 4.

NO – Faulty ECT sensor

G/O Y/Bu

ECT SENSOR (Sensor side/male terminals)

4. ECT Sensor Open Circuit Inspection

Connect the ECM test harness to ECM 33P con-

nector (page 5-13).

Check the continuities between the ECM test harness and ECT 3P sensor connector of the wire side.

Connection: 24 – Yellow/blue

4 – Green/orange

Are there continuities?

YES –

GO TO STEP 5.

NO – • Open circuit in Yellow/blue wire

• Open circuit in Green/orange wire

ECT SENSOR 3P CONNECTOR

(Wire side/female terminals)

Y/Bu

G/O

(24)

(4)

5. ECT Sensor Output Voltage Inspection

Connect the ECT sensor 3P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the ECM test harness terminals.

Connection: 24 (+) – 4 (–)

Standard: 2.7 – 3.1 V (20 ° C/68 ° F)

Is the voltage within 2.7 – 3.1 V (20 ° C/68 ° F)?

YES – • Loose or poor contact on the ECM connector

• Intermittent failure

NO – Replace the ECM with a known good one, and recheck.

(24) (4)

5-35

FUEL SYSTEM (PGM-FI)

MIL 8 BLINKS (TP SENSOR)

1. Sensor Unit Power Line Inspection

Check the sensor unit power line inspection

(page 5-16).

Is the sensor unit power line normal?

YES –

GO TO STEP 2.

NO – Replace or repair the abnormal circuit.

2. TP Sensor Output Voltage

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the TP sensor output voltage at the

ECM test harness terminals.

Connection: 5 (+) – 4 (–)

Standard:

0.29 – 0.71 V (throttle fully closed)

4.13 – 4.76 V (throttle fully opened)

Is there standard voltage?

YES – • Intermittent failure

• Loose or poor contact on the ECM

33P connector

NO –

GO TO STEP 3.

3. TP Sensor Output Line Short Circuit Inspection

Turn the ignition switch OFF.

Disconnect the sensor unit 5P connector.

Check for continuity between the sensor unit 5P connector of the wire side and ground.

Connection: Yellow/black – Ground

Is there continuity?

YES – Short circuit in Yellow/black wire

NO –

GO TO STEP 4.

(4)

Y/Bl

(5)

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

4. TP Sensor Voltage Input Line Open Circuit

Inspection

Check for continuity between the sensor unit 5P connector of the wire side and ECM test harness.

Connection: 5 – Yellow/black

Is there continuity?

YES – Faulty sensor unit (TP sensor)

NO – Open circuit in Yellow/black wire

(5)

Y/Bl

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

5-36

FUEL SYSTEM (PGM-FI)

MIL 9 BLINKS (IAT SENSOR)

1. Sensor Unit Power Line Inspection

Check the sensor unit power line inspection

(page 5-16).

Is the sensor unit power line normal?

YES –

GO TO STEP 2.

NO – Replace or repair the abnormal circuit.

2. IAT Sensor Output Voltage Inspection 1

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the ECM test harness terminals.

Connection: 14 (+) – 4 (–)

Standard: 2.7 – 3.1 V (20 ° C/68 ° F)

Is the voltage within 2.7 – 3.1 V (20 ° C/68 ° F)?

YES – • Intermittent failure

• Loose or poor contact on the ECM

33P connector

NO –

GO TO STEP 3.

(14) (4)

3. IAT Sensor Output Voltage Inspection 2

Turn the ignition switch OFF.

Disconnect the sensor unit 5P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the sensor unit 5P connector of the wire side.

Connection: Gray/blue (+) – Green/orange (–)

Standard: 4.75 – 5.25 V

Is the voltage within 4.75 – 5.25 V?

YES –

GO TO STEP 6.

NO –

GO TO STEP 4.

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminals)

Gr/Bu G/O

4. IAT Sensor Voltage Input Line Short Circuit

Inspection

Check for continuity between the sensor unit 5P connector of the wire side and ground.

Connection: Gray/blue – Ground

Is there continuity?

YES – Short circuit in Gray/blue wire

NO –

GO TO STEP 5.

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

Gr/Bu

5-37

FUEL SYSTEM (PGM-FI)

5. IAT Sensor Voltage Input Line Open Circuit

Inspection

Check for continuity at the Gray/blue wire between the sensor unit 5P connector of the wire side and ECM test harness.

Connection: 14 – Gray/blue

Is there continuity?

YES –

GO TO STEP 6.

NO – Open circuit in Gray/blue wire

SENSOR UNIT 5P CONNECTOR

(Wire side/female terminal)

Gr/Bu

(14)

6. IAT Sensor Resistance Inspection

Turn the ignition switch OFF.

Connect the sensor unit 5P connector.

Measure the resistance at the ECM test harness terminals (at 20 ° C/68 ° F).

Connection: 14 – 4

Standard: 1.13 – 1.88 k Ω (20 ° C/68 ° F)

Is the resistance within 1.13 – 1.88 k Ω (20 ° C/

68 ° F)?

YES – Replace the ECM with a known good one, and recheck.

NO – Faulty sensor unit (IAT sensor)

(14) (4)

MIL 12 BLINKS (INJECTOR)

• Before starting the inspection, check for loose or poor contact on the injector 2P connector and recheck the MIL blinking.

1. Injector Input Voltage Inspection

Turn the ignition switch OFF.

Disconnect the injector 2P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage between the injector 2P connector of the wire side and ground.

Connection: Black/white (+) – Ground (–)

Standard: Battery voltage

Does the standard voltage exist?

YES –

GO TO STEP 2.

NO – Open or short circuit in Black/white wire

INJECTOR 2P CONNECTOR

(Wire side/female terminal)

Bl/W

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FUEL SYSTEM (PGM-FI)

2. Injector Signal Line Short Circuit Inspection

Turn the ignition switch OFF.

Check for continuity between the injector 2P connector of the wire side and ground.

Connection: Pink/green – Ground

Is there continuity?

YES – Short circuit in Pink/green wire

NO –

GO TO STEP 3.

INJECTOR 2P CONNECTOR

(Wire side/female terminal)

P/G

3. Injector Resistance Inspection

Measure the resistance between the injector 2P connector terminals.

Standard: 9 – 12 Ω (20 ° C/68 ° F)

Is the resistance within 9 – 12

Ω

(20

°

C/68

°

F)?

YES –

GO TO STEP 4.

NO – Faulty injector

INJECTOR 2P CONNECTOR

(Injector side/male terminals)

4. Injector Signal Line Open Circuit Inspection

Connect the ECM test harness to the ECM 33P connector.

Check the continuity between the ECM test harness and injector 2P connector of the wire side.

Connection: 16 – Pink/green

Is there continuity?

YES – Replace the ECM with a known good one, and recheck.

NO – Open circuit in Pink/green wire

(16)

INJECTOR 2P CONNECTOR

(Wire side/female terminal)

P/G

5-39

FUEL SYSTEM (PGM-FI)

MIL 21 BLINKS (O

2

SENSOR)

• Do not get grease, oil or other materials in the O

2 sensor air hole.

• Do not reuse O

2

sensor cord, if the O

2

sensor cap is disconnected, replace the O

2

sensor cord with a new one.

• Before starting the inspection, check for loose or poor contact on the O

2

sensor 2P connector or O

2 sensor cap and recheck the MIL blinking.

1. O

2

Sensor System Inspection

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Start the engine and warm up the engine up to coolant temperature is 80 ° C (176 ° F).

Test-ride the motorcycle and recheck the MIL blinking.

Does the MIL blink 21 times?

YES –

GO TO STEP 2.

NO – Intermittent failure

2. O

2

Sensor Short Circuit Inspection

Turn the ignition switch OFF.

Disconnect the O

2

sensor 2P connector (page 7-

5).

Check for continuity between the O

2

sensor 2P connector of the wire side and ground.

Connection: Black/orange – Ground

Is there continuity?

YES – Short circuit in Black/orange wire

NO –

GO TO STEP 3.

O

2

SENSOR 2P CONNECTOR

(Wire side/male terminal)

3. O

2

Sensor Open Circuit Inspection

Connect the ECM test harness to the ECM 33P connector.

Check the continuity between the ECM test harness and O

2

sensor 2P connector of the wire side.

Connection: 3 – Black/orange

Is there continuity?

YES –

GO TO STEP 4.

NO – Open circuit in Black/orange wire

(3)

O

2

SENSOR 2P CONNECTOR

(Wire side/male terminal)

5-40

FUEL SYSTEM (PGM-FI)

4. O

2

Sensor Inspection

Replace the O

2

sensor and O

2

sensor cord with a

known good one (page 5-67).

Disconnect the ECM test harness and connect the ECM 33P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Start the engine and warm up the engine up to coolant temperature is 80 ° C (176 ° F).

Test-ride the motorcycle and recheck the MIL blinking.

Does the MIL blink 21 times?

YES – Replace the ECM with a known good one, and recheck.

NO – Faulty original O

2

sensor and/or O

2

sensor cord

MIL 29 BLINKS (IACV)

• Before starting the inspection, check for loose or poor contact on the IACV 4P connector and recheck the MIL blinking.

1. IACV Resistance Inspection

Turn the ignition switch OFF.

Disconnect the IACV 4P connector.

Measure the resistance at the IACV 4P connector terminals.

Connection: Blue/black – Blue/red

Pink/black – Brown/yellow

Standard: 110 – 150 Ω (25 ° C/77 ° F)

Is the resistance within 110 – 150 Ω (25 ° C/77 ° F)?

YES –

GO TO STEP 2.

NO – Faulty IACV

IACV 4P CONNECTOR

(IACV side/male terminals)

Bu/R

Br/Y P/Bl

Bu/Bl

2. IACV Short Circuit Inspection

Check for continuities between the IACV 4P connector of the wire side and ground.

Connection: Blue/black – Ground

Pink/black – Ground

Brown/yellow – Ground

Blue/red – Ground

Is there continuity?

YES – • Short circuit in Blue/black or Pink/ black wire

• Short circuit in Brown/yellow or

Blue/red wire

NO –

GO TO STEP 3.

IACV 4P CONNECTOR

(Wire side/female terminals)

Bu/Bl

P/Bl Br/Y

Bu/R

5-41

FUEL SYSTEM (PGM-FI)

3. IACV Open Circuit Inspection

Connect the ECM test harness to ECM 33P connector.

Check the continuities between the ECM test harness and IACV 4P connector of the wire side.

Connection: 20 – Pink/black

21 – Blue/black

31 – Brown/yellow

32 – Blue/red

Is there continuity?

YES – Replace the ECM with a known good one, and recheck.

NO – • Open circuit in Blue/black or Pink/ black wire

• Open circuit in Brown/yellow or

Blue/red wire

Bu/Bl Bu/R

(21)

(20)

(31) (32)

P/Bl Br/Y

IACV 4P CONNECTOR

(Wire side/female terminals)

MIL 54 BLINKS (BANK ANGLE

SENSOR)

• Before starting the inspection, check for loose or poor contact on the bank angle sensor 3P connector and recheck the MIL blinking.

1. Bank Angle Sensor Power Input Voltage

Inspection

Turn the ignition switch OFF.

Disconnect the bank angle sensor 3P connector.

Turn the ignition switch ON (and engine stop switch " ": CM and U type).

Measure the voltage at the bank angle sensor connector of the wire side.

Connection: White/red (+) – Green/orange (–)

Standard: 4.75 – 5.25 V

Is there within 4.75 – 5.25 V?

YES –

GO TO STEP 4.

NO –

GO TO STEP 2.

BANK ANGLE SENSOR 3P CONNECTOR

(Wire side/female terminals)

W/R G/O

2. Bank Angle Sensor Input Voltage Line Short

Circuit Inspection

Turn the ignition switch OFF.

Check the continuity between the bank angle sensor 3P connector of the wire side and ground.

Connection: White/red – Ground

Is there continuity?

YES –

GO TO STEP 3.

NO – Short circuit in White/red wire

BANK ANGLE SENSOR 3P CONNECTOR

(Wire side/female terminal)

W/R

5-42

FUEL SYSTEM (PGM-FI)

3. Bank Angle Sensor Input Voltage Line Open

Circuit Inspection

Connect the ECM test harness to the ECM 33P connector.

Check the continuities between the ECM test harness and bank angle sensor 3P connector of the wire side.

Connection: 6 – White/red

4 – Green/orange

Is there continuity?

YES – Replace the ECM with a known good one, and recheck.

NO – • Open circuit in White/red wire

• Open circuit in Green/orange wire

(4) (6)

W/R

G/O

BANK ANGLE SENSOR 3P CONNECTOR

(Wire side/female terminals)

4. Bank Angle Sensor Output Line Short Circuit

Inspection

Turn the ignition switch OFF.

Check the continuity between the bank angle sensor 3P connector of the wire side and ground.

Connection: Red/blue – Ground

Is there continuity?

YES – Short circuit in Red/blue wire

NO –

GO TO STEP 5.

BANK ANGLE SENSOR 3P CONNECTOR

(Wire side/female terminal)

R/Bu

5. Bank Angle Sensor Output Line Open Circuit

Inspection

Connect the ECM test harness to the ECM 33P connector.

Check the continuity between the ECM test harness and bank angle sensor 3P connector of the wire side.

Connection: 26 – Red/blue

Is there continuity?

YES – Open circuit in Red/blue wire

NO –

Inspect the bank angle sensor (page 5-

65).

(26)

R/Bu

BANK ANGLE SENSOR 3P CONNECTOR

(Wire side/female terminal)

5-43