Component Tests and General Diagnostics

POWER SUPPLY AND GROUND CIRCUIT

Description

Supplies power to 4WD system.


Diagnosis Procedure


1. CHECK TRANSFER CONTROL UNIT POWER SUPPLY (1)

1.Turn the ignition switch OFF.
2.Disconnect transfer control unit harness connector.
3.Check the voltage between transfer control unit harness connector and ground.





4.Turn the ignition switch ON.

CAUTION:
Never start the engine.
5.Check the voltage between transfer control unit harness connector and ground.





Is the inspection result normal?
YES- GO TO 3.
NO- GO TO 2.

2. CHECK TRANSFER CONTROL UNIT POWER SUPPLY (2)

1.Turn the ignition switch OFF.
2.Check the 10A fuse (#34).
3.Check the harness for open or short between transfer control unit harness connector No.20 terminal and
10A (#34).
Is the inspection result normal?
YES- Perform the trouble diagnosis for power supply circuit. Refer to "Wiring Diagram BATTERY POWER SUPPLY -" Battery Power Supply.
NO- Repair or replace error-detected parts.

3. CHECK TRANSFER CONTROL UNIT POWER SUPPLY (3)

1.Turn the ignition switch OFF.
2.Check the voltage between transfer control unit harness connector and ground.





3.Turn the ignition switch ON.

CAUTION:
Never start the engine.
4.Check the voltage between transfer control unit harness connector and ground.





Is the inspection result normal?
YES- GO TO 5.
NO- GO TO 4.

4. CHECK TRANSFER CONTROL UNIT POWER SUPPLY (4)

1.Turn the ignition switch OFF.
2.Check the 10A fuse (#56).
3.Disconnect IPDM E/R harness connector.
4.Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.





5.Check the continuity between transfer control unit harness connector and the ground.





Is the inspection result normal?
YES- Perform the trouble diagnosis for ignition power supply circuit. Refer to "Wiring Diagram IGNITION POWER SUPPLY -" Ignition Power Supply.
NO- Repair or replace error-detected parts.

5. CHECK TRANSFER MOTOR POWER SUPPLY

1.Turn the ignition switch OFF.
2.Check the voltage between transfer control unit harness connector and ground.





3.Turn the ignition switch ON.

CAUTION:
Never start the engine.
4.Check the voltage between transfer control unit harness connector and ground.





Is the inspection result normal?
YES- GO TO 7.
NO- GO TO 6.

6. CHECK TRANSFER MOTOR POWER SUPPLY CIRCUIT

1.Turn the ignition switch OFF.
2.Check the 30A fusible link (J).
3.Check the harness for open or short between transfer control unit harness connector No.41 terminal and
30A fusible link (J).
Is the inspection result normal?
YES- Perform the trouble diagnosis for power supply circuit. Refer to "Wiring Diagram BATTERY POWER SUPPLY -" Battery Power Supply.
NO- Repair or replace error-detected parts.

7. CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (1)

1.Turn the ignition switch OFF.
2.Disconnect 4WD switch assembly harness connector.
3.Check the voltage between 4WD switch assembly harness connector and ground.





4.Turn the ignition switch ON.

CAUTION:
Never start the engine.
5.Check the voltage between 4WD switch assembly harness connector and ground.





Is the inspection result normal?
YES- GO TO 9.
NO- GO TO 8.

8. CHECK 4WD SWITCH ASSEMBLY POWER SUPPLY (2)

1.Turn the ignition switch OFF.
2.Check the 10A fuse (#13).
3.Disconnect fuse block (J/B) harness connector.
4.Check the continuity between transfer control unit harness connector and IPDM E/R harness connector.





5.Check the continuity between transfer control unit harness connector and the ground.





Is the inspection result normal?
YES- Perform the trouble diagnosis for ignition power supply circuit. Refer to "Wiring Diagram IGNITION POWER SUPPLY -" Ignition Power Supply.
NO- Repair or replace error-detected parts.

9. CHECK TRANSFER CONTROL UNIT GROUND

1.Turn the ignition switch OFF.
2.Check the voltage between transfer control unit harness connector and ground.





3.Check the continuity between transfer control unit harness connector and ground.





Is the inspection result normal?
YES- GO TO 10.
NO- Repair or replace error-detected parts.

10. CHECK 4WD SWITCH ASSEMBLY GROUND

1.Turn the ignition switch OFF.
2.Check the voltage between transfer control unit harness connector and ground.





Is the inspection result normal?
YES- INSPECTION END
NO- Repair or replace error-detected parts.