4WD Warning Lamp Does Not Turn On

4WD WARNING LAMP DOES NOT TURN ON

Description

4WD warning lamp does not turn ON when turning ignition switch to ON.


Diagnosis Procedure

Regarding Wiring Diagram information, [1][2]Electrical Diagrams.

1. CHECK TRANSFER CONTROL UNIT POWER SUPPLY AND GROUND CIRCUITS

P1801.
Are the inspection results normal?
YES- GO TO 2.
NO- Perform repairs as necessary.

2. 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 terminals and ground.










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





Are the inspection results normal?
YES - GO TO 3.
NO-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 terminal 16

3. CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER

1.Turn ignition switch "OFF". (Stay for at least 5 seconds.)





2.Check continuity between transfer control unit harness connector M153 terminal 38 and combination meter harness connector
M24 terminal 26.
Continuity should exist.
Also check harness for short to ground and short to power.
Is there continuity?
YES - GO TO 4.
NO- Repair or replace damaged parts.

4. 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 terminal using suitable wiring.
-Transfer control unit harness connector M153 terminal 38 and ground.
Does the indicator lamp turn on?
YES- GO TO 5.
NO- Replace the combination meter. Service and Repair.

5. SYMPTOM CHECK

Check again.
Does the symptom still occur?
YES- GO TO 6.
NO- Inspection End.

6. CHECK TRANSFER CONTROL UNIT

Check transfer control unit input/output signal. Pinout Values and Diagnostic Parameters.
Are the inspection results normal?
YES- Inspection End.
NO- Check transfer control unit pin terminals for damage or loose connection with harness connector.
If any items are damaged, repair or replace damaged parts.