Diagnostic Procedure

WARNING: This page is about a different car, the 2003 Nissan Altima. However, it is still accessible from the selected car via links, so may be relevant.

CHECK DTC WITH ECM
- Check P code.
  Turn ignition switch ON and select "SELF-DIAGNOSTIC RESULTS" mode for "ENGINE" with CONSULT-II.
  
  Refer to TESTING PROCEDURE .
OK or NG
1. OK (with CONSULT-II): GO TO 2.
2. OK (without CONSULT-II): GO TO 4.
3. NG: Check ignition signal circuit for engine control. Refer to IGNITION SYSTEM .
CHECK INPUT SIGNAL (WITH CONSULT-II)
With CONSULT-II
1. Start engine.
2. Select "TCM INPUT SIGNALS" in "DATA MONITOR" mode for "A/T" with CONSULT-II.
3. Read out the value of "ENGINE SPEED".
  Check engine speed changes according to throttle position.
OK or NG
1. OK: GO TO 6.
2. NG: GO TO 3.
Fig 1: Checking Input Signal (With Consult-II)
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING ITEM
Check the following items:
- Harness for short or open between TCM and ECM
- Resistor and ignition coil
  Refer to IGNITION SYSTEM .
OK or NG
1. OK: GO TO 6.
2. NG: Repair or replace damaged parts.
CHECK INPUT SIGNAL (WITHOUT CONSULT-II)
Without CONSULT-II
1. Start engine.
2. Check voltage between TCM terminal 39 (W/G) and ground.
  Voltage : 0.6 (Idle speed) - 2.2V (3, 000 rpm)
OK or NG
1. OK: GO TO 6.
2. NG: GO TO 5.
Fig 2: Checking Voltage Between TCM Terminal 39 (W/G) And Ground
Courtesy of NISSAN MOTOR CO., U.S.A.
DETECT MALFUNCTIONING ITEM
Check the following items:
- Harness for short or open between TCM and ECM
- Resistor and ignition coil
  Refer to IGNITION SYSTEM .
OK or NG
1. OK: GO TO 6.
2. NG: Repair or replace damaged parts.
CHECK DTC
Perform "DIAGNOSTIC TROUBLE CODE (DTC) CONFIRMATION PROCEDURE ".

OK or NG
1. OK: INSPECTION END
2. NG: GO TO 7.
CHECK TCM INSPECTION
1. Perform TCM input/output signal inspection.
2. If NG, recheck TCM pin terminals for damage or loose connection with harness connector.
OK or NG
1. OK: INSPECTION END
2. NG: Repair or replace damaged parts.