Diagnostic Procedure

WARNING: This page is about a different car, the 2007 Nissan Pathfinder. However, it is still accessible from the selected car via links, so may be relevant.

CHECK TRANSFER CONTROL UNIT POWER SUPPLY CIRCUIT

Turn ignition switch "OFF". (Stay for at least 5 seconds.)
Connect transfer control unit harness connector.

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

CONNECTOR TERMINAL VOLTAGE REFERENCE

Connector	Terminal	Voltage (Approx.)
M152	16 - Ground	0V
M152	22 - Ground
M153	29 - Ground
	30 - Ground	Battery voltage
	47 - Ground	Battery voltage

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

Turn ignition switch "ON". (Do not start engine.)

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

CONNECTOR TERMINAL VOLTAGE REFERENCE

Connector	Terminal	Voltage (Approx.)
M152	16 - Ground	Battery voltage
M152	22 - Ground
M153	29 - Ground
	30 - Ground	0V
	47 - Ground	Battery voltage

Fig 2: Checking 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.

10A fuses [No. 21 located in fuse block (J/B) and No. 59 located in the fuse and relay box. Refer to "POWER SUPPLY ROUTING CIRCUIT ".
Harness for short or open between battery and transfer control unit harness connector M153 terminals 47.
Harness for short or open between ignition switch and transfer control unit harness connector M153 terminal 29.
Harness for short or open between battery and transfer shut off relay harness connector E155 terminal 1 and 3.
Harness for short or open between transfer shut off relay harness connector E155 terminal 2 and transfer control unit harness connector M153 terminal 30.
Harness for short or open between transfer shut off relay harness connector E155 terminal 5 and transfer control unit harness connector M152 terminals 16 and 22.
Battery and ignition switch. Refer to "POWER SUPPLY ROUTING CIRCUIT ".
Transfer shut off relay. Refer to "COMPONENT INSPECTION ".

CHECK TRANSFER CONTROL UNIT 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 M152 terminals 3 and 6, and M153 terminal 45 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.

Fig 3: Checking Continuity Between Transfer Control Unit Harness Connector M152 Terminals 3 And 6, And M153 Terminal 45

CHECK COMBINATION METER POWER SUPPLY CIRCUIT

Turn ignition switch "OFF". (Stay for at least 5 seconds.)
Disconnect transfer control unit harness connector.

Check voltage between combination meter harness connector terminal and ground.

CONNECTOR TERMINAL VOLTAGE REFERENCE

Connector	Terminal	Voltage (Approx.)
M24	16 - Ground	0V

Fig 4: Checking Voltage Between Combination Meter Harness Connector Terminal And Ground

Turn ignition switch "ON". (Do not start engine.)

Check voltage between combination meter harness connector terminal and ground.

CONNECTOR TERMINAL VOLTAGE REFERENCE

Connector	Terminal	Voltage (Approx.)
M24	16 - Ground	Battery voltage

Fig 5: Checking Voltage Between Combination Meter Harness Connector Terminal 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)]. Refer to "POWER SUPPLY ROUTING CIRCUIT ".
Harness for short or open between ignition switch and combination meter harness connector M24 terminal 16.
Ignition switch. Refer to "POWER SUPPLY ROUTING CIRCUIT ".

CHECK HARNESS BETWEEN TRANSFER CONTROL UNIT AND COMBINATION METER
1. Turn ignition switch "OFF". (Stay for at least 5 seconds.)
2. Disconnect transfer control unit harness connector and combination meter harness connector.
3. Check continuity between the following terminals.
  - Transfer control unit harness connector M152 terminal 2 and combination meter harness connector M24 terminal 30.
  - Transfer control unit harness connector M152 terminal 11 and combination meter harness connector M24 terminal 27.
  - Transfer control unit harness connector M152 terminal 12 and combination meter harness connector M24 terminal 29.
  - Transfer control unit harness connector M152 terminal 21 and combination meter harness connector M24 terminal 28.
    Continuity should exist.
    
    Also check harness for short to ground and short to power.
    
    Fig 6: Checking Continuity Between Transfer Control Unit Connector M152 Terminal 2 And Combination Meter Connector M24 Terminal 30
OK or NG

OK: GO TO 5.

NG: Repair or replace damaged parts.
CHECK INDICATOR LAMP CIRCUIT
1. Connect combination meter harness connector.
2. Disconnect transfer control unit harness connector.
3. Turn ignition switch "ON".
4. Ground the following terminals using suitable wiring.
  - Transfer control unit harness connector M152 terminal 2 and ground.
  - Transfer control unit harness connector M152 terminal 11 and ground.
  - Transfer control unit harness connector M152 terminal 12 and ground.
  - Transfer control unit harness connector M152 terminal 21 and ground.
    
    Fig 7: Checking Transfer Control Unit Harness Connector E152 Terminal 2,11, 12, 21 And Ground
Do indicator lamps turn on?

OK: GO TO 6.

NG: Replace combination meter. Refer to "COMBINATION METER ".
SYMPTOM CHECK
Check again.

OK or NG

OK: Inspection End.

NG: GO TO 7.
CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to "TRANSFER CONTROL UNIT INPUT/OUTPUT SIGNAL REFERENCE VALUES ".

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.