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Home >> Infiniti >> 2003 >> Q45 >> Repair and Diagnosis >> Body & Frame >> Windows >> Rear Window Defogger >> Rear Window Defogger Switch Circuit Check.
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Rear Window Defogger Switch Circuit Check.

  1. CHECK REAR WINDOW DEFOGGER (MULTI-FUNCTION) SWITCH 

    With CONSULT-II 

    Check rear window defogger switch "REAR DEF SW" in the "DATA MONITOR  " mode with CONSULT-II.

    1. When rear window defogger switch ON 
    2. REAR DEF SW: ON 
    Fig 1: Checking Rear Window Defogger (Multi-Function) Switch With CONSULT-II
    G02045166Courtesy of NISSAN MOTOR CO., U.S.A.

    With out CONSULT-II 

    1. Turn ignition switch ON.
    2. Check voltage between BCM connector and ground.
      Fig 2: BCM Connector Terminal And Ground Voltage Specifications
      G02045167Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK >> Rear window defogger switch is OK.
    2. NG >> GO TO 2
    Fig 3: Checking Rear Window Defogger (Multi-Function) Switch Without CONSULT-II
    G02045168Courtesy of NISSAN MOTOR CO., U.S.A.
  2. REAR WINDOW DEFOGGER SWITCH SIGNAL CIRCUIT INSPECTION 
    1. Turn ignition switch OFF.
    2. Disconnect BCM and multifunction switch (rear window defogger with) connectors.
    3. Check continuity between BCM connector M4 terminal 10 and multifunction switch (rear defogger switch) connector M83 terminal 5.
      1. 10 (G/R) - 5(G/R) :Continuity should exist 
      Fig 4: Checking Continuity Between BCM Connector M4 Terminal 10 And Multifunction Switch (Rear Defogger Switch) Connector M83 Terminal 5
      G02045169Courtesy of NISSAN MOTOR CO., U.S.A.
    4. Check continuity between BCM harness connector M4 terminal 10 and ground
      1. 10 (G/R) - Ground :Continuity should not exist 

    OK or NG 

    1. OK >> GO TO 3.
    2. NG >> Repair or replace harness between BCM and multifunction switch (rear window defogger switch).
  3. MULTIFUNCTION (REAR WINDOW DEFOGGER) SWITCH GROUND HARNESS INSPECTION 

    Check continuity between multi-function switch (rear window defogger switch) connector M83 terminal 2 and ground.

    1. 2(B) - ground :Continuity should exist 
    Fig 5: Checking Continuity Between Multi-Function Switch (Rear Window Defogger Switch) Connector M83 Terminal 2 And Ground
    G02045170Courtesy of NISSAN MOTOR CO., U.S.A.

    OK or NG 

    1. OK >> Replace multi function switch.
    2. NG >> Repair or replace harness between multifunction switch (rear window defogger switch) and ground.