2003 Infiniti Q45FACTORY OEM SERVICE PROCEDURE

Encoder Circuit Check (Driver Side)

  1. CHECK FRONT POWER WINDOW REGULATOR (DRIVER SIDE) CIRCUIT 
    1. Turn ignition switch ON.
    2. Check voltage between front power window regulator (driver side) connector D7 terminal 4 and ground.
      1. 4 (W) - Ground : Approx. 10V 
      Fig 1: Checking Voltage Between Front Power Window Regulator (Driver Side) Connector D7 Terminal 4 And Ground
      G02045095Courtesy 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 driver door control unit (LCU01) and front power window regulator (driver side) connector.
    3. Check continuity between driver door control unit (LCU01) connector D8 terminal 4 and front power window regulator (driver side) connector D7 terminal 4.
      1. 4 (W) - 4 (W) : Continuity should exist. 
      Fig 2: Checking Continuity Between Driver Door Control Unit (LCU01) Connector D8 Terminal 4 And Front Power Window Regulator (Driver Side) Connector D7 Terminal 4
      G02045096Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG? 

    1. OK >> Replace driver door control unit (LCU01).
    2. NG >> Repair or replace harness between driver door control unit (LCU01) and front power window regulator (driver side).
  3. CHECK ENCODER GROUND 
    1. Turn ignition switch OFF.
    2. Disconnect front power window regulator (driver side) connector.
    3. Check continuity between front power window regulator (driver side) connector D7 terminal 6 and ground.
      1. 4 (B) - Ground : Continuity should exist. 
      Fig 3: Checking Continuity Between Front Power Window Regulator (Driver Side) Connector D7 Terminal 6 And Ground
      G02045097Courtesy 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 (driver side) connector.
    2. Turn ignition switch ON.
    3. Check the signal between driver door control unit (LCU01) connector and ground with oscilloscope.
      Fig 4: Signal Specification Between Driver Door Control Unit (LCU01) Connector And Ground
      G02045098Courtesy 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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