WINDOW DEFOGGER SYSTEM Rear Window Defogger System does not Operate

DESCRIPTION

When the window defogger switch on the air conditioning control assembly is pressed, the operation signal is transmitted to the air conditioning amplifier assembly via LIN communication. When the air conditioning amplifier assembly receives the signal, it turns on the defogger relay to operate the window defogger system.

WIRING DIAGRAM

B006LZHE05

CAUTION / NOTICE / HINT

Note


  • Inspect the fuses for circuits related to this system before performing the following procedure.

  • The window defogger system uses the LIN communication system. Inspect the communication function by following How to Proceed with Troubleshooting. Troubleshoot the window defogger system after confirming that the communication system is functioning properly.

    Click here

  • If the battery voltage becomes low, window defogger operation is canceled to prioritize supplying power to the power steering system.

    Click here

PROCEDURE


  1. CHECK AIR CONDITIONING SYSTEM


    1. Check the air conditioning system.

      Click here

      Tech Tips

      Both the window defogger system operation signal and air conditioning system operation signal are transmitted to the air conditioning amplifier assembly via the same communication line.

      OK
      The air conditioning system operates normally.
      Result
      Proceed to
      OK
      NG

    NG

    GO TO AIR CONDITIONING SYSTEM Click here

    OK

  2. CHECK AIR CONDITIONING CONTROL ASSEMBLY


    1. Check that the defogger indicator illuminates when the window defogger switch is on.

      OK
      Defogger indicator illuminates.
      Result
      Proceed to
      OK
      NG

    NG

    REPLACE AIR CONDITIONING CONTROL ASSEMBLY Click here

    OK

  3. PERFORM ACTIVE TEST USING GTS


    1. Using the GTS, perform the Active Test.

      Click here


      Body Electrical > Air Conditioner > Active Test
      Tester Display Measurement Item Control Range Diagnostic Note
      Defogger Relay (Rear) Defogger relay OFF or ON -

      Body Electrical > Air Conditioner > Active Test
      Tester Display
      Defogger Relay (Rear)
      OK
      Back door glass (window defogger wire) warms up.
      Result
      Proceed to
      OK
      NG

    NG

    CHECK HARNESS AND CONNECTOR (BACK DOOR GLASS [WINDOW DEFOGGER WIRE] - BATTERY) Click here

    OK

  4. CHECK AIR CONDITIONING AMPLIFIER ASSEMBLY


    1. Temporarily replace the air conditioning amplifier assembly with a new or normally functioning one.


    2. Check that the window defogger system operates normally.

      OK
      The window defogger system operates normally.
      Result
      Proceed to
      OK
      NG

    OK

    END (AIR CONDITIONING AMPLIFIER ASSEMBLY IS DEFECTIVE)

    NG

    REPLACE AIR CONDITIONING CONTROL ASSEMBLY Click here

  5. CHECK HARNESS AND CONNECTOR (BACK DOOR GLASS [WINDOW DEFOGGER WIRE] - BATTERY)


    1. B006MG2C02
      *a

      Front view of wire harness connector

      (to Back Door Glass [Window Defogger Wire])

      Disconnect the back door glass (window defogger wire) connector.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Switch Condition Specified Condition
      VU1-1 - Body ground Engine switch on (IG), window defogger switch on 11 to 14 V
      Engine switch on (IG), window defogger switch off Below 1 V
      Result
      Proceed to
      OK
      NG

    OK

    REPLACE BACK DOOR GLASS (DEFOGGER WIRE) Click here

    NG

  6. INSPECT DEFOGGER RELAY


    1. Remove the defogger relay from the engine room relay block.

    2. Inspect the defogger relay.

      Click here

      Result
      Proceed to
      OK
      NG

    NG

    REPLACE DEFOGGER RELAY

    OK

  7. CHECK HARNESS AND CONNECTOR (DEFOGGER RELAY - BATTERY)


    1. B006KUKC01
      *a

      Front view of wire harness connector

      (to Defogger Relay)

      Remove the defogger relay from the engine room relay block.

    2. Measure the voltage according to the value(s) in the table below.

      Standard Voltage
      Tester Connection Condition Specified Condition
      Defogger relay terminal 2 - Body ground Engine switch on (IG) 11 to 14 V
      Defogger relay terminal 5 - Body ground Always 11 to 14 V
      Result
      Proceed to
      OK
      NG

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  8. CHECK HARNESS AND CONNECTOR (DEFOGGER RELAY - AIR CONDITIONING AMPLIFIER ASSEMBLY AND BACK DOOR GLASS)


    1. Remove the defogger relay from the engine room relay block.

    2. Disconnect the VU1 back door glass (window defogger wire) connector.

    3. Disconnect the G36 air conditioning amplifier assembly connector.

    4. Measure the resistance according to the value(s) in the table below.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Defogger relay terminal 1 - G36-38 (RDEF) Always Below 1 Ω
      Defogger relay terminal 3 - VU1-1 Always Below 1 Ω
      Defogger relay terminal 1 or G36-38 (RDEF) - Body ground Always 10 kΩ or higher
      Defogger relay terminal 3 or VU1-1 - Body ground Always 10 kΩ or higher
      Result
      Result Proceed to
      OK (for LHD) A
      OK (for RHD) B
      NG C

    A

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    B

    REPLACE AIR CONDITIONING AMPLIFIER ASSEMBLY Click here

    C

    REPAIR OR REPLACE HARNESS OR CONNECTOR