Diagnostic Procedure

WARNING: This page is about a different car, the 2005 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.

CHECK DTC WITH ECM
- Check P code with CONSULT-II "ENGINE".
  Turn ignition switch ON and select "SELF-DIAGNOSTIC RESULTS" mode for "ENGINE" with CONSULT-II.
  
  Refer to "MALFUNCTION INDICATOR LAMP (MIL) ".
OK or NG
- OK (with CONSULT-II): GO TO 2.
- OK (without CONSULT-II): GO TO 4.
- NG: Check ignition signal circuit for engine control. Refer to "IGNITION SIGNAL ".
CHECK INPUT SIGNAL (WITH CONSULT-II)
With CONSULT-II
1. Start engine.
2. Select "DATA MONITOR" mode for "A/T" with CONSULT-II.
  
  Fig 1: Consult -II - (DATA MONITOR) Display
  Courtesy of NISSAN MOTOR CO., U.S.A.
3. Read out the value of "ENGINE SPEED".
  Check engine speed changes according to throttle position.
OK or NG
- OK: GO TO 5.
- NG: GO TO 3.
DETECT MALFUNCTIONING ITEM
Check the following items:
- Harness for short or open between TCM and ECM
- Resistor and ignition coil
  Refer to "IGNITION SIGNAL ".
OK or NG
- OK: GO TO 5.
- NG: Repair or replace damaged parts.
CHECK INPUT SIGNAL (WITHOUT CONSULT-II)
Without CONSULT-II
1. Start engine.
2. Check voltage between TCM harness connector E143 terminal 39 (W/G) and ground.
  
  Fig 2: Checking Voltage Between TCM Harness Connector E143 Terminal 39 & Ground
  Courtesy of NISSAN MOTOR CO., U.S.A.
  - Voltage Refer to " ECM INSPECTION TABLE " (ECM terminal 103).
OK or NG
- OK: GO TO 5.
- NG: GO TO 3.
CHECK DTC
Perform "DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE ".

OK or NG
- OK: INSPECTION END
- NG: GO TO 6.
CHECK TCM INSPECTION
1. Perform TCM input/output signal inspection. Refer to "TCM TERMINALS AND REFERENCE VALUE ".
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
- OK: INSPECTION END
- NG: Repair or replace damaged parts.