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Home >> Nissan-Datsun >> 2004 >> Quest SE >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P2122, P2123: App Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  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
      G00775963Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO 2.
    2. NG: Repair or replace ground connections.
  2. CHECK APR SENSOR 1 POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APR) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting Accelerator Pedal Position (Apr) Sensor Harness Connector
      G00775964Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminal 7 and ground with CONSULT-II or tester.
      Fig 3: Checking Voltage Between APP Sensor Terminal And Ground
      G00775965Courtesy of NISSAN MOTOR CO., U.S.A.
      1. Voltage: Approximately 5V 

    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.
  3. CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between ECM terminal 82 and APP sensor terminal 1. Refer to WIRING DIAGRAM  .
      1. Continuity should exist. 
    4. Also check harness for short to ground or short to power.

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 106 and APP sensor terminal 2. Refer to WIRING DIAGRAM  .
      1. Continuity should exist 
    2. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO 5.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  5. CHECK APP SENSOR 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO 6.
    2. NG: Replace accelerator pedal assembly.
  6. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    1. INSPECTION END