Power Supply Circuit For Transfer Control Unit

Power Supply Circuit For Transfer Control Unit

CONSULT-II REFERENCE VALUE IN DATA MONITOR MODE:

TRANSFER CONTROL UNIT TERMINALS AND REFERENCE VALUE:

DIAGNOSTIC PROCEDURE

1. CHECK POWER SUPPLY
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 fuse (No. j, located in the fuse and fusible link box). Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT". PG Diagrams (Power Supply, Ground & Circuit Elements)
^ 10A fuses (No. 21, located in the fuse block-junction block (J/B) and 60 and 61 located in the fuse and relay box). Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT". PG Diagrams (Power Supply, Ground & Circuit Elements)
^ 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. Refer to PG-4, "POWER SUPPLY ROUTING CIRCUIT". PG Diagrams (Power Supply, Ground & Circuit Elements)
^ Transfer shut off relay 1, 2. Refer to TF-225, "COMPONENT INSPECTION".

2. CHECK GROUND CIRCUIT
1. Turn ignition switch "OFF".
2. Disconnect transfer control unit harness connector.





3. Check continuity between transfer control unit harness connector M152 terminals 6 and 18, and 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 TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TF-211, "Transfer Control Unit Input/Output Signal Reference Values". Pinout Values and Diagnostic Parameters
OK or NG
OK >> GO TO 4.
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.

4. CHECK DTC
Perform the self-diagnosis, after driving a vehicle for a while.
OK or NG
OK >> Inspection End.
NG >> Replace transfer control unit.

COMPONENT INSPECTION
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Remove transfer shut off relay 1 and transfer shut off relay 2.








3. Apply 12V direct current between transfer shut off relay terminals 1 and 2.
4. Check continuity between relay terminals 3 and 5.
5. If NG, replace the transfer shut off relay 1 or 2.