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Diagnostic Procedure

WARNING: This page is about a different car, the 2004 Nissan Quest. However, it is still accessible from the selected car via links, so may be relevant.
  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground three screws on the body. Refer to GROUND INSPECTION  .
      Fig 1: Loosing And Retighten Ground Three Screws On Body
      G00884113Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: Repair or replace ground connections.
  2. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-I 
    1. Check voltage between ECM terminal 3 and ground under the following conditions with CONSULT-II or tester.
      Fig 2: Checking Voltage Between ECM Terminal 3 And Ground
      G00884114Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 3: Identifying Voltage Based On Switch Position
      G00884115Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  10 .
    2. NG: GO TO 3.
  3. CHECK THROTTLE CONTROL MOTOR RELAY INPUT SIGNAL CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Disconnect IPDM E/R harness connector E124.
    4. Check continuity between ECM terminal 3 and IPDM E/R terminal 42. Refer to WIRING DIAGRAM  .

      Continuity should exist. 

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

    OK or NG 

    1. OK: GO TO  5 .
    2. NG: GO TO 4.
  4. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E5, F14
    • Harness for open or short between ECM and IPDM E/R
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  5. CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT-I 
    1. Reconnect all harness connectors disconnected.
    2. Check voltage between ECM terminal 104 and ground with CONSULT-II or tester.
      Fig 4: Checking Voltage Between ECM Terminal 104 And Ground
      G00884116Courtesy of NISSAN MOTOR CO., U.S.A.

      Voltage: Battery voltage 

    OK or NG 

    1. OK: GO TO  9 .
    2. NG: GO TO 6.
  6. CHECK THROTTLE CONTROL MOTOR RELAY POWER SUPPLY CIRCUIT-II 
    1. Disconnect ECM harness connector.
    2. Disconnect IPDM E/R harness connector E121.
    3. Check continuity between ECM terminal 104 and IPDM E/R terminal 47. Refer to WIRING DIAGRAM  .

      Continuity should exist. 

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

    OK or NG 

    1. OK: GO TO  8 .
    2. NG: GO TO 7.
  7. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness for open or short between ECM and IPDM E/R
      1. Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK FUSE 
    1. Disconnect 15A fuse.
    2. Check 15A fuse for blown.

    OK or NG 

    1. OK: GO TO 9.
    2. NG: Replace 15A fuse.
  9. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    OK or NG 

    1. OK: Replace IPDM E/R. Refer to POWER DISTRIBUTION .
    2. NG: Repair or replace harness or connectors.
  10. CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect electric throttle control actuator harness connector.
    3. Disconnect ECM harness connector.
    4. Check harness continuity between the following terminals. Refer to WIRING DIAGRAM  .
      Fig 5: Disconnecting ECM Harness Connector
      G00884117Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 6: Identifying Air Duct
      G00884118Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO 11.
    2. NG: Repair or replace.
  11. CHECK ELECTRIC THROTTLE CONTROL ACTUATOR VISUALLY 
    1. Remove the intake air duct.
    2. Check if foreign matter is caught between the throttle valve and the housing.

    OK or NG 

    1. OK: GO TO 12.
    2. NG: Remove the foreign matter and clean the electric throttle control actuator inside.
      Fig 7: Removing Intake Air Duct
      G00884119Courtesy of NISSAN MOTOR CO., U.S.A.
  12. CHECK THROTTLE CONTROL MOTOR 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO 13.
    2. NG: GO TO  14 .
  13. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    OK or NG 

    1. OK: GO TO 14.
    2. NG: Repair or replace harness or connectors.
  14. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 
    1. Replace the electric throttle control actuator.
    2. Perform THROTTLE VALVE CLOSED POSITION LEARNING  .
    3. Perform IDLE AIR VOLUME LEARNING  .
      1. INSPECTION END 
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