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Home >> Infiniti >> 2004 >> I35 >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System >> DTC P2122 & DTC P2123: App Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. RETIGHTEN GROUND SCREWS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten engine ground screws. See Figure .
    1. : GO TO 2.
  2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON
      Fig 1: Locating Accelerator Pedal Position Sensor
      G00787416Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminals 6 and ground with CONSULT-II or tester.
      Fig 2: Checking Voltage Between APP Sensor Terminal And Ground
      G00787417Courtesy of NISSAN MOTOR CO., U.S.A.

    Voltage: Approximately 5V 

    OK or NG 

    1. OK: GO TO  4 .
    2. NG: GO TO 3.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M229, F66
    • Harness for open or short between ECM and accelerator pedal position sensor
      1. : Repair open circuit or short to ground or short to power in harness or connectors.
  4. CHECK APP SENSOR 1 GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between APP sensor terminal 3 and engine ground.

      Refer to Wiring Diagram.

      Continuity should exist. 

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

      OK or NG 

      1. OK: GO TO  6 .
      2. NG: GO TO 5.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M229, F66
    • Joint connector-20
    • Harness for open or short between ECM and accelerator pedal position sensor.

    OK or NG 

    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  6. CHECK APP SENSOR 1 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 73 and APP sensor terminal 5.

      Refer to Wiring Diagram

      Continuity should exist. 

    3. 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 connectors M229, F66
    • Harness for open or short between ECM and accelerator pedal position sensor

    OK or NG 

    1. : Repair open circuit or short to ground or short to power in harness or connectors.
  8. CHECK APP SENSOR 

    Refer to COMPONENT INSPECTION  .

    OK or NG 

    1. OK: GO TO 9.
    2. NG: Replace accelerator pedal assembly.
  9. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  .

    OK or NG 

    1. : INSPECTION END
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