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Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> DTC P2138: 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
      G00779515Courtesy of NISSAN MOTOR CO., U.S.A.
      1. GO TO 2.
  2. CHECK APP SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting Accelerator Pedal Position (APP) Sensor Harness Connector
      G00779516Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminals 1, 2 and ground with CONSULT-II or tester.

      Voltage: Approximately 5V 

      4. Fig 3: Checking Voltage Between APP Sensor Terminals 1, 2 & Ground
      G00779517Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK: GO TO  4.
    2. NG: GO TO 3.
  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 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 4, ECM terminal 83 and APP sensor terminal 5.

      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  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 INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between ECM terminal 106 and APP sensor terminal 3, ECM terminal 98 and APP sensor terminal 6.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    2. 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 the accelerator pedal position sensor.
  9. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    1. INSPECTION END 
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