4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON

4WD Shift Indicator Lamp and 4LO Indicator Lamp Do Not Turn ON

SYMPTOM: 4WD shift indicator lamp and 4LO indicator lamp do not turn ON for approximately 1 second when turning ignition switch to "ON".

DIAGNOSTIC PROCEDURE
1. CHECK TRANSFER CONTROL UNIT POWER SUPPLY CIRCUIT
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector.





3. Check voltage between transfer control unit harness connector terminals and ground.








4. Turn ignition switch "ON". (Do not start engine.)
5. Check voltage between transfer control unit harness connector terminals and ground.





OK or NG
OK >> GO TO 2.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
^ 40A fusible link (No. j, located in the fuse and fusible link box).
^ 10A fuses [No. 21, located in the fuse block (J/B) and Nos. 57 and 58 located in the fuse and relay box].
^ Harness for short or open between battery and transfer control unit harness connector M152 terminal 19.
^ Harness for short or open between battery and transfer shut off relay 2 harness connector E157 terminal 1 and 3.
^ Harness for short or open between battery and transfer shut off relay 1 harness connector E156 terminal 3.
^ Harness for short or open between ignition switch and transfer control unit harness connector M152 terminal 25.
^ Harness for short or open between ignition switch and transfer shut off relay 1 harness connector E156 terminal 1.
^ Harness for short or open between transfer shut off relay 2 harness connector E157 terminal 5 and transfer control unit harness connector M153 terminals 44, 45.
^ Harness for short or open between transfer shut off relay 1 harness connector E156 terminal 5 and transfer control unit harness connector M153 terminals 44, 45.
^ Harness for short or open between transfer shut off relay 2 harness connector E157 terminal 2 and transfer control unit harness connector M153 terminal 40.
^ Harness for open between transfer shut off relay 1 harness connector E156 terminal 2 and ground.
^ Battery and ignition switch.
^ Transfer shut off relay 1, 2.
2. CHECK TRANSFER CONTROL UNIT GROUND CIRCUIT
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connectors.





3. Check continuity between transfer control unit harness connector M152 terminals 6, 18, M153 terminal 32 and ground.
Continuity should exist.
Also check harness for short to power.
OK or NG
OK >> GO TO 3.
NG >> Repair open circuit or short to power in harness or connectors.
3. CHECK COMBINATION METER POWER SUPPLY CIRCUIT
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect combination meter harness connector.





3. Check voltage between combination meter harness connector M24 terminal 16 and ground.








4. Turn ignition switch "ON". (Do not start engine.)
5. Check voltage between combination meter harness connector M24 terminal 16 and ground.





OK or NG
OK >> GO TO 4.
NG >> Check the following. If any items are damaged, repair or replace damaged parts.
^ 10A fuse [No. 14, located in the fuse block (J/B) or] ignition switch.
^ Harness for short or open between ignition switch and combination meter harness connector M24 terminal 16
4. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)





2. Check continuity between the following terminals.
^ Transfer control unit harness connector M153 terminal 35 and combination meter harness connector M24 terminal 30.
^ Transfer control unit harness connector M153 terminal 36 and combination meter harness connector M24 terminal 27.
^ Transfer control unit harness connector M153 terminal 37 and combination meter harness connector M24 terminal 29.
Continuity should exist.
Also check harness for short to ground and short to power.
OK or NG
OK >> GO TO 5.
NG >> Repair or replace damaged parts.
5. CHECK INDICATOR LAMP CIRCUIT
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Connect combination meter harness connector.
3. Disconnect transfer control unit harness connector.
4. Turn ignition switch "ON". (Do not start engine.)





5. Ground the following terminals using suitable wiring.
- Transfer control unit harness connector M153 terminal 35 and ground.
- Transfer control unit harness connector M153 terminal 36 and ground.
- Transfer control unit harness connector M153 terminal 37 and ground.
Do indicator lamps turn on?
OK >> GO TO 6.
NG >> Replace the combination meter.
6. SYMPTOM CHECK
Check again.
OK or NG
OK >> Inspection End.
NG >> GO TO 7.
7. CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal.
OK or NG
OK >> Inspection End.
NG >> Check transfer control unit pin terminals for damage or loose connection with harness connector. If any items are damaged, repair or replace damaged parts.