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Home >> Infiniti >> 2004 >> FX35 RWD >> Repair and Diagnosis >> Engine Performance >> Engine Control System >> DTC P0122 & P0123 TP Sensor >> Diagnostic Procedure
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Diagnostic Procedure

  1. Check Ground Connections 
    1. Turn ignition switch OFF.
    2. Loosen and retighten three ground screws on the body. See Figure. Refer to GROUND INSPECTION .

    OK or NG

    1. OK: Go to 2.
    2. NG: Repair or replace ground connections.

  2. Check Throttle Position Sensor 2 Power Supply Circuit-I 
    1. Disconnect electric throttle control actuator harness connector. See Figure.
    2. Turn ignition switch ON.
    3. Check voltage between electric throttle control actuator terminal 1 and ground with CONSULT-II or tester.
      Fig 1: Testing Electric Throttle Control Actuator Reference Voltage
      G00729409Courtesy of NISSAN MOTOR CO., U.S.A.

    Voltage: Approximately 5V 

    OK or NG

    1. OK: Go to  7.
    2. NG: Go to 3.

  3. Check Throttle Position Sensor 2 Power Supply Circuit-II 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between electric throttle control actuator terminal 1 and ECM terminal 47. Refer to wiring diagram. See Figure.

      Continuity should exist  .

    OK or NG

    1. OK: Go to 4.
    2. NG: Repair or replace open circuit.

  4. Check Throttle Position Sensor 2 Power Supply Circuit-III 

    Check the following.

    • Harness for short to power and short to ground, between the following terminals.
      THROTTLE POSITION SENSOR 2 CIRCUIT TESTS

      ECM Terminal Sensor See
      47 Electric Throttle Control Actuator Terminal 1 (1)
      91 APP Sensor Terminal 2 (2)
      (1) See WIRING DIAGRAM 
      (2) See WIRING DIAGRAM 

    OK or NG

    1. OK: Go to 5.
    2. NG: Repair short to ground or short to power in harness or connectors.

  5. Check APP Sensor 

    Refer to COMPONENT INSPECTION .

    OK or NG

    1. OK: Go to  11.
    2. NG: Go to 6.

  6. 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 .
      1. Inspection end
  7. Check Throttle Position Sensor 2 Ground Circuit For Open And Short 
    1. Turn ignition switch OFF.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between electric throttle control actuator terminal 5 and ECM terminal 66. Refer to wiring diagram. See Figure.

      Continuity should exist  .

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

    OK or NG

    1. OK: Go to 8.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.

  8. Check Throttle Position Sensor 2 Input Signal Circuit For Open And Short 
    1. Check harness continuity between ECM terminal 69 and electric throttle control actuator terminal 2. Refer to wiring diagram. See Figure.

      Continuity should exist  .

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

    OK or NG

    1. OK: Go to 9.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.

  9. Check Throttle Position Sensor 

    Refer to COMPONENT INSPECTION .

    OK or NG

    1. OK: Go to  11.
    2. NG: Go to 10.

  10. Replace Electric Throttle Control Actuator 
    1. Replace the electric throttle control actuator.
    2. Perform THROTTLE VALVE CLOSED POSITION LEARNING .
    3. Perform IDLE AIR VOLUME LEARNING .
      1. Inspection end 
  11. Check Intermittent Incident 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    1. Inspection end 
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