LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Nissan-Datsun >> 2004 >> Sentra SE-R >> Repair and Diagnosis >> Engine Performance >> System >> Engine Control System - Qr25DE >> DTC P1128: Throttle Control Motor >> Diagnostic Procedure
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Diagnostic Procedure

  1. RETIGHTEN GROUND SCREWS 
    1. Turn ignition switch OFF.
    2. Loosen and retighten engine ground screws.
    Fig 1: Identifying Engine Ground
    G00778132Courtesy of NISSAN MOTOR CO., U.S.A.
    1. GO TO 2.
  2. CHECK THROTTLE CONTROL MOTOR OUTPUT SIGNAL CIRCUIT FOR OPEN OR SHORT 
    1. Turn ignition switch OFF.
    2. Disconnect electric throttle control actuator harness connector.
    3. Disconnect ECM harness connector.
    4. Check harness continuity between the following terminals. Refer to WIRING DIAGRAM .
      Fig 2: Disconnecting Electric Throttle Control Actuator Harness Connector
      G00778134Courtesy of NISSAN MOTOR CO., U.S.A.
      Fig 3: Electric Throttle Control Actuator Terminal Continuity Table
      G00778133Courtesy of NISSAN MOTOR CO., U.S.A.
    5. Also check harness for short to ground and short to power.

    OK or NG 

    1. OK: GO TO 3.
    2. NG: Repair open circuit or short to ground or short to power in harness or connectors.
  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