Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Titan. However, it is still accessible from the selected car via links, so may be relevant.

CHECK POWER SUPPLY
1. Turn ignition switch "OFF".
2. Disconnect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector terminal and ground.
  
  Fig 1: Test Conditions
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 2: Checking Voltage
  Courtesy of NISSAN MOTOR CO., U.S.A.
4. Turn ignition switch "ON". (Do not start engine.)
5. Check voltage between transfer control unit harness connector terminals and ground.
Fig 3: Voltage Chart
Courtesy of NISSAN MOTOR CO., U.S.A.

Fig 4: Checking Voltage
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 2.
2. NG: Check the following. If any items are damaged, repair or replace damaged parts.
- 10A fuse [No. 26 or 59, located in the IPDM E/R]
- Harness for short or open between battery and transfer control unit harness connector terminal 27
- Harness for short or open between ignition switch and transfer relay 1 harness connector E46 terminal 2 (L/W)
- Harness for short or open between ignition switch and transfer control unit harness connector terminal 25
- Harness for short or open between transfer relay 1 harness connector E46 terminal 1 (B) and ground
- Battery and ignition switch. Refer to POWER DISTRIBUTION in SYSTEM WIRING DIAGRAMS - TITAN article in ELECTRICAL .
- Transfer relay 1. Refer to COMPONENT INSPECTION .
CHECK GROUND CIRCUIT
1. Disconnect transfer control unit harness connector.
2. Check continuity between transfer control unit harness connector E143 terminal 32 (B) and ground.
Continuity should exist.

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

OK or NG
1. OK: GO TO 3.
2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
Fig 5: Checking Continuity
Courtesy of NISSAN MOTOR CO., U.S.A.
CHECK POWER SUPPLY SIGNAL
1. Turn ignition switch "OFF".
2. Connect transfer control unit harness connector.
3. Check voltage between transfer control unit harness connector terminal and ground.
  
  Fig 6: Test Conditions
  Courtesy of NISSAN MOTOR CO., U.S.A.
  
  Fig 7: Checking Voltage
  Courtesy of NISSAN MOTOR CO., U.S.A.
4. Turn ignition switch "ON". (Do not start engine.)
5. Check voltage between transfer control unit harness connector terminal and ground.
Fig 8: Voltage Chart
Courtesy of NISSAN MOTOR CO., U.S.A.

OK or NG
1. OK: GO TO 4.
2. NG: Check the following. If any items are damaged, repair or replace damaged parts.
Fig 9: Checking Voltage
Courtesy of NISSAN MOTOR CO., U.S.A.
- Harness for short or open between battery and transfer control unit harness connector terminal 40
- Transfer relay 2. Refer to COMPONENT INSPECTION .
CHECK TRANSFER CONTROL UNIT
Check transfer control unit input/output signal. Refer to TRANSFER CONTROL UNIT INPUT/OUTPUT SIGNAL REFERENCE VALUES .

OK or NG
1. OK-1: With CONSULT-II: GO TO 5.
2. OK-2: Without CONSULT-II: GO TO 6.
3. 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.
PERFORM SELF-DIAGNOSIS (WITH CONSULT-II)
1. Turn ignition switch "ON". (Do not start engine.)
2. Select "SELF-DIAG RESULTS" mode for "ALL MODE AWD/4WD" with CONSULT-II.
3. Touch "ERASE".
4. Turn ignition switch "OFF" and wait at least 10 seconds.
5. Perform the self-diagnosis again.
Is the "SHIFT ACT CIR [P1819]" displayed?
1. YES: Replace transfer control unit. Refer to TRANSFER CONTROL UNIT .
2. NO: INSPECTION END
PERFORM SELF-DIAGNOSIS (WITHOUT CONSULT-II)
1. Perform the self-diagnosis and then erase self-diagnostic results. Refer to SELF-DIAGNOSTIC PROCEDURE (WITHOUT CONSULT-II) and ERASE SELF-DIAGNOSIS .
2. Perform the self-diagnosis again.
Do the self-diagnostic results indicate transfer control device?
1. YES: Replace transfer control unit. Refer to TRANSFER CONTROL UNIT .
2. NO: INSPECTION END