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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> DTC P2127, P2128: 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.
      Fig 1: Identifying Engine Ground
      G00779491Courtesy of NISSAN MOTOR CO., U.S.A.
      1. GO TO 2.
  2. CHECK APP SENSOR 2 POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting APP Sensor Harness Connector
      G00779492Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminal 1 and ground with CONSULT-II or tester.

      Voltage: Approximately 5V 

    OK or NG 

    1. OK: GO TO  4.
    2. NG: GO TO 3.
    Fig 3: Checking Voltage Between APP Sensor Terminal 1 & Ground
    G00779493Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M59, F27
    • 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 2 GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Check harness continuity between APP sensor terminal 83 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  6.
    2. NG: GO TO 5.
  5. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors M59, F27
    • 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.
  6. CHECK APP SENSOR 2 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Disconnect ECM harness connector.
    2. Check harness continuity between ECM terminal 98 and APP sensor terminal 6. 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 M59, F27
    • 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.
  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 ".

    1. INSPECTION END 
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