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Home >> Infiniti >> 2010 >> M45 Base >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - DTCS P1550 To P2A03 >> DTC P2122, P2123 App Sensor >> Diagnosis Procedure
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Diagnosis Procedure

  1. CHECK GROUND CONNECTIONS
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground screws on the body.

    Refer to "GROUND INSPECTION ".

    Fig 1: Identifying Body Ground (M70 And M16)
    G06303438Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO 2.

    NG: Repair or replace ground connections.

  2. CHECK APP SENSOR 1 POWER SUPPLY CIRCUIT
    1. Disconnect accelerator pedal position (APP) sensor (1) harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Accelerator Pedal Position (APP) Sensor Harness Connector
      G05209977Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminal 4 and ground with CONSULT-III or tester.

    Voltage: Approximately 5 V 

    OK or NG 

    OK: GO TO  4.

    NG: GO TO 3.

    Fig 3: Checking Voltage Between APP Sensor Terminal 4 And Ground
    G04925503Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and accelerator pedal position sensor

    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. Disconnect ECM harness connector.
    3. Check harness continuity between APP sensor terminal 2 and ECM terminal 82.

      Refer to SYSTEM WIRING DIAGRAMS article.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  6.

    NG: GO TO 5.

  5. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and accelerator pedal position sensor

    Repair open circuit or short to ground or short to power in harness or connectors.

  6. CHECK APP SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT
    1. Check harness continuity between ECM terminal 106 and APP sensor terminal 3.

      Refer to SYSTEM WIRING DIAGRAMS article.

      Continuity should exist  .

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

    OK or NG 

    OK: GO TO  8.

    NG: GO TO 7.

  7. DETECT MALFUNCTIONING PART

    Check the following.

    • Harness connectors E108, M15
    • Harness for open or short between ECM and accelerator pedal position sensor

    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 

    OK: GO TO  10.

    NG: GO TO 9.

  9. REPLACE ACCELERATOR PEDAL ASSEMBLY
    1. Replace accelerator pedal assembly.
    2. Perform "ACCELERATOR PEDAL RELEASED POSITION LEARNING ".
    3. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
    4. Perform "IDLE AIR VOLUME LEARNING ".

    INSPECTION END 

  10. CHECK INTERMITTENT INCIDENT

    Refer to "DIAGNOSIS PROCEDURE ".

    INSPECTION END 

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