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Home >> Nissan-Datsun >> 2004 >> Sentra Base, Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - QG18DE >> DTC P1229: Sensor Power Supply >> Diagnostic Procedure
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Diagnostic Procedure

  1. RETIGHTEN GROUND SCREWS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten engine ground screws.
      1. GO TO 2.
    Fig 1: Retightening Engine Ground Screws
    G00773114Courtesy of NISSAN MOTOR CO., U.S.A.
  2. CHECK THROTTLE POSITION SENSOR POWER SUPPLY CIRCUIT 
    1. Disconnect electric throttle control actuator harness connector.
    2. Turn ignition switch ON.
      Fig 2: Disconnecting Electric Throttle Control Actuator Harness Connector
      G00773115Courtesy of NISSAN MOTOR CO., U.S.A.
    3. Check voltage between electric throttle control actuator terminal 1 and ground with CONSULT-II or tester.
      1. Voltage: Approximately 5V 

    OK or NG 

    1. OK: GO TO  4.
    2. NG: GO TO 3.
    Fig 3: Checking Voltage Between Electric Throttle Control Actuator Terminal 1 And Ground
    G00773116Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK SENSOR POWER SUPPLY CIRCUITS FOR SHORT 

    Check the following.

    • Harness for short to power and short to ground between ECM terminal 47 and electric throttle control actuator terminal 1.
    • ECM pin terminal.

    OK or NG 

    1. OK: GO TO 4.
    2. NG: Repair short to ground or short to power in harness or connectors.
  4. CHECK THROTTLE POSITION SENSOR 

    Refer to COMPONENT INSPECTION .

    OK or NG 

    1. OK: GO TO  6.
    2. NG: GO TO 5.
  5. REPLACE ELECTRIC THROTTLE CONTROL ACTUATOR 
    1. Replace electric throttle control actuator.
    2. Perform THROTTLE VALVE CLOSED POSITION LEARNING .
    3. Perform IDLE AIR VOLUME LEARNING .
      1. INSPECTION END 
  6. CHECK INTERMITTENT INCIDENT 

    Refer to TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT .

    1. INSPECTION END