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Home >> Infiniti >> 2008 >> FX35 AWD >> Repair and Diagnosis >> Engine Performance >> Engine Control Systems >> Engine Control System - DTCS P1212 Through P2A03 (VQ35DE) >> DTC P2138 App Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. CHECK GROUND CONNECTIONS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten ground screw on the body. Refer to "GROUND INSPECTION ".
    Fig 1: Identifying Body Ground, Steering Column And Blower Motor
    G05216304Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    OK: GO TO  2.

    NG: Repair or replace ground connections.

  2. CHECK ACCELERATOR PEDAL POSITION SENSOR 1 POWER SUPPLY CIRCUIT 
    1. Disconnect accelerator pedal position (APP) sensor harness connector.
    2. Turn ignition switch ON.
      Fig 2: Identifying Accelerator Pedal Position Sensor Harness Connector
      G05216752Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between APP sensor terminals 6 and ground with CONSULT-III or tester.

      Voltage: Approximately 5V 

    OK or NG 

    OK: GO TO  4.

    NG: GO TO  3.

    Fig 3: Checking Voltage Between APP Sensor Terminal 6 And Ground
    G04875310Courtesy of NISSAN MOTOR CO., U.S.A.
  3. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • Harness for open or short between ECM and APP sensor

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

  4. CHECK ACCELERATOR PEDAL POSITION SENSOR 2 POWER SUPPLY CIRCUIT-I 

    Check voltage between APP sensor terminal 4 and ground with CONSULT-III or tester.

    Voltage: Approximately 5V 

    OK or NG 

    OK: GO TO  10.

    NG: GO TO  5.

    Fig 4: Checking Voltage Between APP Sensor Terminal 4 And Ground
    G04875435Courtesy of NISSAN MOTOR CO., U.S.A.
  5. CHECK ACCELERATOR PEDAL POSITION SENSOR 2 POWER SUPPLY CIRCUIT-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between APP sensor terminal 4 and ECM terminal 91.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

    OK or NG 

    OK: GO TO  7.

    NG: GO TO  6.

  6. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • Harness for open or short between ECM and APP sensor

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

  7. CHECK ACCELERATOR PEDAL POSITION SENSOR 2 POWER SUPPLY CIRCUIT-III 

    Check the following.

    • Harness for short to power and short to ground, between the following terminals.
    ECM AND SENSOR TERMINALS REFERENCE

    ECM terminal Sensor terminal Reference Wiring Diagram
    91 APP sensor terminal 4 WIRING DIAGRAM 
    47 Electric throttle control actuator terminal 1 WIRING DIAGRAM

    OK or NG 

    OK: GO TO  8.

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

  8. CHECK THROTTLE POSITION SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  16.

    NG: GO TO  9.

  9. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 
    1. Replace electric throttle control actuator.
    2. Perform "THROTTLE VALVE CLOSED POSITION LEARNING ".
    3. Perform "IDLE AIR VOLUME LEARNING ".

      >> INSPECTION END 

  10. CHECK ACCELERATOR PEDAL POSITION SENSOR GROUND CIRCUIT FOR OPEN AND SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between the following;

      APP sensor terminals 3 and ECM terminal 82,

      APP sensor terminal 1 and ECM terminal 83.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  12.

    NG: GO TO  11.

  11. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • Harness for open or short between ECM and APP sensor

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

  12. CHECK ACCELERATOR PEDAL POSITION SENSOR INPUT SIGNAL CIRCUIT FOR OPEN AND SHORT 
    1. Check harness continuity between the following;

      ECM terminal 106 and APP sensor terminal 5,

      ECM terminal 98 and APP sensor terminal 2.

      Refer to WIRING DIAGRAM .

      Continuity should exist. 

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

    OK or NG 

    OK: GO TO  14.

    NG: GO TO  13.

  13. DETECT MALFUNCTIONING PART 

    Check the following.

    • Harness connectors E211, M41
    • Harness for open or short between ECM and APP sensor

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

  14. CHECK ACCELERATOR PEDAL POSITION SENSOR 

    Refer to "COMPONENT INSPECTION ".

    OK or NG 

    OK: GO TO  16.

    NG: GO TO  15.

  15. 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 

  16. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT ".

    >> INSPECTION END 

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