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Home >> Nissan-Datsun >> 2008 >> Sentra SE-R >> Repair and Diagnosis >> Body & Frame >> Windows >> Glass, Window System & Mirrors >> Rear Window Defogger >> Rear Window Defogger Switch Circuit Check
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Rear Window Defogger Switch Circuit Check

  1. CHECK REAR WINDOW DEFOGGER SWITCH OPERATION 

    With CONSULT-III 

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

    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-III 

    1. Turn ignition switch ON.
    2. Check voltage between BCM connector and ground.
      CONNECTOR TERMINAL VOLTAGE SPECIFICATION

      Connector Terminals Condition Voltage (V) (Approx.)
      (+) (-)
      M18 10 Ground Rear window defogger switch is pressed 0
      Rear window defogger switch is released 5

    OK or NG 

    OK: Rear window defogger switch check is OK.

    NG: GO TO 2.

    Fig 1: Checking Voltage Between BCM Connector And Ground
    G04927940Courtesy of NISSAN MOTOR CO., U.S.A.
  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. 

    OK or NG 

    OK: GO TO 3.

    NG: Repair or replace harness.

    Fig 2: Checking Continuity Between BCM Connector M18 Terminal 10 And Ground
    G04927941Courtesy of NISSAN MOTOR CO., U.S.A.
  3. CHECK REAR WINDOW DEFOGGER SWITCH 

    Check continuity between front air control terminals.

    CONNECTOR TERMINAL CONTINUITY SPECIFICATION

    Terminals Condition Continuity
    38 3 Rear window defogger switch is ON (pressed) Yes
    Rear window defogger switch is OFF (released) No

    OK or NG 

    OK: GO TO 4.

    NG: Replace front air control. Refer to "FRONT AIR CONTROL ".

    Fig 3: Checking Continuity Between Front Air Control Terminals
    G04927942Courtesy of NISSAN MOTOR CO., U.S.A.
  4. CHECK REAR WINDOW DEFOGGER SWITCH GROUND 

    Check continuity between front air control connector and ground.

    CONNECTOR TERMINAL CONTINUITY SPECIFICATION

    Connector Terminal Ground Continuity
    M33 3 Yes

    OK or NG 

    OK: GO TO 5.

    NG: Repair or replace harness.

    Fig 4: Checking Continuity Between Front Air Control Connector And Ground
    G04927943Courtesy of NISSAN MOTOR CO., U.S.A.
  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 

    OK or NG 

    OK: Replace front air control. Refer to "FRONT AIR CONTROL ".

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

    Fig 5: Checking Voltage Between BCM Connector M18 Terminal 10 And Ground
    G04927940Courtesy of NISSAN MOTOR CO., U.S.A.
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