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Window Defogger System: Inspection

  1. INSPECT AIR CONDITIONING CONTROL ASSY 
    1. Inspect operation of the defogger switch indicator.
      Fig 1: Inspecting Operation Of Defogger Switch Indicator
      G02813963Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 2: Specified Condition Table
      G02813967Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the result is not as specified, replace the air conditioning control assy.

    2. Inspect the defogger switch continuity.
      Fig 3: Inspecting Defogger Switch Continuity
      G02813964Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 4: Terminal Specified Condition Table
      G02813968Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the result is not as specified, replace the air conditioning control assy.

  2. INSPECT OUTER REAR VIEW MIRROR ASSY LH (W/ OUTER MIRROR HEATER) 
    1. Inspect operation of the mirror defogger operation.
      Fig 5: Inspecting Outer Rear View Mirror Assy LH (W/ Outer Mirror Heater)
      G02813965Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 6: Specified Condition Table
      G02813969Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the result is not as specified, replace the mirror assy.

  3. INSPECT OUTER REAR VIEW MIRROR ASSY RH (W/ OUTER MIRROR HEATER) 
    1. Inspect operation of the mirror defogger operation.
      Fig 7: Inspecting Outer Rear View Mirror Assy RH (W/ Outer Mirror Heater)
      G02813966Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 8: Terminal Specified Condition Table
      G02813970Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the result is not as specified, replace the mirror assy.

  4. INSPECT BACK WINDOW (DEFOGGER WIRE) 
    NOTE:
    • When cleaning the glass, using a soft and dry cloth wipe the glass along of the wire. Take care not to damage the wires.
    • Do not use detergents or glass cleaners including abrasive ingredients.
    • When measuring voltage, wrap a piece of tin foil around the tip of the negative probe and press the foil against the wire with your finger, as shown in Fig 9.
      Fig 9: Pressing Foil Against Wire With Finger
      G02813971Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch ON.
    2. Turn the defogger switch ON.
    3. Inspect the voltage at the center of each heat wire as shown in Fig 10.
      Fig 10: Inspecting Voltage At Center Of Each Heat Wire
      G02813972Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      STANDARD

      Voltage Criteria
      Approx. 5 V Okay wire is not broken
      Approx. 10 V or 0 V Wire is not broken
      NOTE:

      If there is approximately 10 V, the wire maybe broken between the center of the wire and the positive (+) end. If there is no voltage, the wire maybe broken between the center of the wire and ground.

    4. Place the voltmeter positive (+) lead against the defogger wire on the battery side.
      Fig 11: Placing Voltmeter Negative (-) Lead With Foil Strip Against Wire On Ground Side
      G02813973Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    5. Place the voltmeter negative (-) lead with the foil strip against the wire on the ground side.
    6. Slide the positive (+) lead from battery to ground side.
    7. The point where the voltmeter deflects from several V to 0 V is the place where the defogger wire is broken.
      NOTE:

      If the defogger wire is not broken, the voltmeter indicates 0 V at the positive (+) end of the defogger wire but gradually increases to about 12 V as the meter probe moves to the other end.

    8. If necessary, repair the defogger wire.
      1. Clean the broken wire tips with grease, wax and silicone remover.
      2. Place the masking tape along the both sides of the wire.
        Fig 12: Cleaning Broken Wire Tips With Grease, Wax And Silicone Remover
        G02813974Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      3. Thoroughly mix the repair agent (DuPont paste No. 4817).
      4. Using a fine tip brush, apply a small amount of the agent to the wire.
        Fig 13: Applying Small Amount Of Agent To Wire
        G02813975Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      5. After a few minutes, remove the masking tape.
        NOTE: Do not repair the defogger wire for at least 24 hours.
  5. INSPECT DEFOGGER RELAY (Marking: DEF) 
    1. Inspect the continuity.
      Fig 14: Inspecting Continuity
      G02813976Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      Fig 15: Terminal Specified Condition Table
      G02813977Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      If the result is not as specified, replace the relay.