2003 Infiniti Q45FACTORY OEM SERVICE PROCEDURE

Encoder Circuit Check (Passenger Side)

  1. CHECK FRONT POWER WINDOW REGULATOR (PASSENGER SIDE) CIRCUIT 
    1. Turn ignition switch ON.
    2. Check voltage between front power window regulator (passenger side) connector D37 terminal 4 and ground.
      1. 4 (W) - Ground : Approx. 10V 
      Fig 1: Checking Voltage Between Front Power Window Regulator (Passenger Side) Connector D37 Terminal 4 And Ground
      G02045101Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG? 

    1. OK >> GO TO  3
    2. NG >> GO TO 2
  2. CHECK HARNESS CONTINUITY 
    1. Turn ignition switch OFF.
    2. Disconnect passenger door control unit and front power window regulator (passenger side) connector.
    3. Check continuity between passenger door control unit connector D38 terminal 15 and front power window regulator (passenger side) connector D37 terminal 4.
      1. 15 (W) - 4 (W) : Continuity should exist. 
      Fig 2: Checking Continuity Between Passenger Door Control Unit Connector D38 Terminal 15 And Front Power Window Regulator (Passenger Side) Connector D37 Terminal 4
      G02045102Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG? 

    1. OK >> Replace passenger door control unit.
    2. NG >> Repair or replace harness between passenger door control unit and front power window regulator (passenger side).
  3. CHECK ENCODER GROUND 
    1. Turn ignition switch OFF.
    2. Disconnect front power window regulator (passenger side) connector.
    3. Check continuity between front power window regulator (passenger side) connector D37 terminal 6 and ground.
      1. 6 (B) - Ground : Continuity should exist. 
      Fig 3: Checking Continuity Between Front Power Window Regulator (Passenger Side) Connector D37 Terminal 6 And Ground
      G02045103Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG? 

    1. OK >> GO TO 4
    2. NG >> Repair or replace harness.
  4. CHECK ENCODER SIGNAL 
    1. Connect front power window regulator (passenger side) connector.
    2. Turn ignition switch ON.
    3. Check the signal between passenger door control unit connector and ground with oscilloscope.
      Fig 4: Signal Specification Between Passenger Door Control Unit Connector And Ground
      G02045104Courtesy of NISSAN MOTOR CO., U.S.A.
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  • • Brakes feel soft, pull hard to one side, or make grinding noises.
  • • The engine overheats, stalls repeatedly, or misfires under load.
  • • You are missing required tools, torque specs, or safe lifting equipment.
  • • You are not confident in the next step or safety outcome.

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