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Home >> Nissan-Datsun >> 2012 >> Sentra SE-R >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass, Window System & Mirrors >> Service Information >> Rear Window Defogger >> Rear Window Defogger Switch Circuit Inspection
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Rear Window Defogger Switch Circuit Inspection

  1. CHECK REAR WINDOW DEFOGGER SWITCH OPERATION

    With CONSULT 

    Check ("REAR DEF SW", "IGN ON SW") in DATA MONITOR mode with CONSULT.

    When rear window defogger switch is turned to ON REAR DEF SW: ON 

    When ignition switch is turned to ON IGN ON SW: ON 

    Without CONSULT 

    1. Turn ignition switch ON.
    2. Check voltage between BCM connector and ground.
      Connector Terminals Condition Voltage (V) (Approx.)
      (+) (-)
      M18 10 Ground Rear window defogger switch is pressed 0
      Rear window defogger switch is released 5
      Fig 1: Checking Rear Window Defogger Switch Operation
      G04927940Courtesy of NISSAN NORTH AMERICA, INC.

      OK or NG 

      OK: Rear window defogger switch check is OK.

      NG: GO TO 2.

  2. CHECK REAR WINDOW DEFOGGER SWITCH CIRCUIT HARNESS CONTINUITY
    1. Turn ignition switch OFF.
    2. Disconnect BCM and front air control.
    3. Check continuity between BCM connector M18 (A) terminal 10 and front air control connector M33 (B) terminal 38.

      10 - 38: Continuity should exist  .

    4. Check continuity between BCM connector M18 (A) terminal 10 and ground

      10 - Ground: Continuity should not exist  .

      Fig 2: Checking Rear Window Defogger Switch Circuit Harness Continuity
      G04927941Courtesy of NISSAN NORTH AMERICA, INC.

      OK or NG 

      OK: GO TO 3.

      NG: Repair or replace harness.

  3. CHECK REAR WINDOW DEFOGGER SWITCH

    Check continuity between front air control terminals.

    Terminals Condition Continuity
    38 3 Rear window defogger switch is ON (pressed) Yes
    Rear window defogger switch is OFF (released) No
    Fig 3: Checking Rear Window Defogger Switch
    G04927942Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO 4.

    NG: Replace front air control. Refer to , "REMOVAL AND INSTALLATION ".

  4. CHECK REAR WINDOW DEFOGGER SWITCH GROUND

    Check continuity between front air control connector and ground.

    Connector Terminal Ground Continuity
    M33 3 Yes
    Fig 4: Checking Rear Window Defogger Switch Ground
    G04927943Courtesy of NISSAN NORTH AMERICA, INC.

    OK or NG 

    OK: GO TO 5.

    NG: Repair or replace harness.

  5. CHECK BCM OUTPUT SIGNAL
    1. Connect BCM.
    2. Turn ignition switch ON.
    3. Check voltage between BCM connector M18 terminal 10 and ground.

      10 - Ground: Approx. 5V 

      Fig 5: Checking BCM Output Signal
      G04927940Courtesy of NISSAN NORTH AMERICA, INC.

      OK or NG 

      OK: Replace front air control. Refer to , "REMOVAL AND INSTALLATION ".

      NG: Replace BCM. Refer to , "REMOVAL AND INSTALLATION OF BCM ".

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