Diagnosis Procedure

Regarding Wiring Diagram information, refer to "WIRING DIAGRAM ".

1. CHECK POWER SUPPLY 
   1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
   2. Connect transfer control unit harness connector.
   3. Check voltage between transfer control unit harness connector terminals and ground.

      Connector	Terminal	Voltage (Approx.)
      E142	16 - Ground	0V
      	22 - Ground
      E143	29 - Ground
      	30 - Ground	Battery voltage
      	47 - Ground

      Fig 1: Checking Voltage Between Transfer Control Unit Harness Connector Terminals And Ground

      Courtesy of NISSAN NORTH AMERICA, INC.
   4. Turn ignition switch ON. (Do not start engine.)
   5. Check voltage between transfer control unit harness connector terminals and ground.

      Connector	Terminal	Voltage (Approx.)
      E142	16 - Ground	Battery voltage
      	22 - Ground
      E143	29 - Ground
      	30 - Ground	0V
      	47 - Ground	Battery voltage

      Fig 2: Checking Voltage Between Transfer Control Unit Harness Connector Terminals And Ground

      Courtesy of NISSAN NORTH AMERICA, INC.

      Are the inspection results normal? 

      YES: GO TO 2.

      NO: Check the following. If any items are damaged, repair or replace damaged parts.

      • 10A fuses No. 26 located in fuse and fusible link box and No. 59 located in the fuse and relay box.
      • 20A fuse No. 53 located in the IPDM E/R.
      • Harness for short or open between battery and transfer control unit harness connector terminals 47.
      • Harness for short or open between battery and transfer control unit harness connector terminal 29.
      • Harness for short or open between battery and transfer shut off relay harness connector E69 terminal 1, and 5.
      • Harness for short or open between transfer shut off relay harness connector E69 terminal 2 and transfer control unit harness connector terminal 30.
      • Harness for short or open between transfer shut off relay harness connector E69 terminal 3 and transfer control unit harness connector terminals 16 and 22.
      • Battery and ignition switch.
      • Transfer shut off relay. Refer to "COMPONENT INSPECTION ".
2. CHECK GROUND CIRCUIT 
   1. Turn ignition switch OFF. (Stay for at least 5 seconds.)
   2. Disconnect transfer control unit harness connector.
   3. Check continuity between transfer control unit harness connector E142 terminals 3, 6, E143 terminal 45 and ground.

      Continuity should exist. 

      Also check harness for short to ground and short to power.

      Are the inspection results normal? 

      YES: GO TO 3.

      NO: Repair open circuit or short to ground or short to power in harness or connectors.

      Fig 3: Checking Continuity Between Transfer Control Unit Harness Connector E142 Terminals 3, 6, E143 Terminal 45 And Ground

      Courtesy of NISSAN NORTH AMERICA, INC.
3. CHECK TRANSFER CONTROL UNIT 

   Check transfer control unit input/output signal. Refer to "REFERENCE VALUE ".

   Are the inspection results normal? 

   YES: GO TO 4.

   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.

4. CHECK DTC 

   Perform the self-diagnosis, after driving a vehicle for a while.

   Are the inspection results normal? 

   YES: Inspection End.

   NO: Replace transfer control unit. Refer to "REMOVAL AND INSTALLATION ".