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Home >> Infiniti >> 2005 >> FX45 >> Repair and Diagnosis >> Engine Performance >> Engine Control System - VK45DE >> DTC P1128: Throttle Control Motor >> 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.

      Refer to "GROUND INSPECTION  ".

      Fig 1: Checking Ground Connections
      G02361928Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG

    1. OK: GO TO 2.
    2. NG: Repair or replace ground connections.
  2. CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Disconnect electric throttle control actuator harness connector.
    2. Disconnect ECM harness connector.
    3. Check harness continuity between the following terminals. Refer to WIRING DIAGRAM  .
      Fig 2: Electric Throttle Control Actuator And ECM Terminal Continuity Chart
      G02361929Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 3: Disconnecting Electric Throttle Control Actuator Harness Connector
      G02361930Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Also check harness for short to ground and short to power.

    OK or NG

    1. OK: GO TO 3.
    2. NG: Repair or replace.
  3. CHECK THROTTLE CONTROL MOTOR 

    Refer to "COMPONENT INSPECTION  ".

    OK or NG

    1. OK: GO TO 4.
    2. NG: GO TO  5 .
  4. CHECK INTERMITTENT INCIDENT 

    Refer to "TROUBLE DIAGNOSIS FOR INTERMITTENT INCIDENT  ".

    OK or NG

    1. OK: GO TO 5.
    2. NG: Repair or replace harness or connectors.
  5. 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