LEMON Manuals: Even more car manuals for everyone: 1960-2025
Home >> Toyota >> 2006 >> 4Runner SR5, 4.7 T, AWD >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/WINDOWGLASS/Mirror >> Window Defogger System >> Inspection
April 5, 2026: LEMON Manuals is launched! Read the announcement.

Window Defogger System: Inspection

  1. INSPECT AIR CONDITIONING CONTROL ASSY 
    1. Inspect operation of the defogger switch indicator.

      Standard: 

      MEASUREMENT CONDITION SPECIFIED CONDITION TABLE

      Measurement Condition Specified Condition
      Battery positive (+) <==> IG+ (2)
      Battery negative (-) <==> DIND (11)      		 Indicator light comes up

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

      Fig 1: Identifying Defogger Switch Connector Terminals
      G04332126Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Inspect the defogger switch continuity.

      Standard: 

      SWITCH CONDITION SPECIFIED CONDITION TABLE

      Terminal No. Switch Condition Specified Condition
      4 <==> 7 ON Continuity
      4 <==> 7 OFF No continuity

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

      Fig 2: Identifying Defogger Switch Connector Terminals
      G04332127Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  2. INSPECT OUTER REAR VIEW MIRROR ASSY LH (W/OUTER MIRROR HEATER) 
    1. Inspect the mirror defogger operation.

      Standard: 

      MEASUREMENT CONDITION SPECIFIED CONDITION TABLE

      Measurement Condition Specified Condition
      Battery positive (+) <==> H+ (4)
      Battery negative (-) <==> H- (5)      		 Mirror becomes warm

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

      Fig 3: Inspecting Mirror Defogger Operation (1 Of 2)
      G04332128Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  3. INSPECT OUTER REAR VIEW MIRROR ASSY RH (W/ OUTER MIRROR HEATER) 
    1. Inspect the mirror defogger operation.

      Standard: 

      MEASUREMENT CONDITION SPECIFIED CONDITION TABLE

      Measurement Condition Specified Condition
      Battery positive (+) <==> H+ (4)
      Battery negative (-) <==> H- (5)      		 Mirror becomes warm

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

      Fig 4: Inspecting Mirror Defogger Operation (2 Of 2)
      G04332129Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  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 5.
      Fig 5: Pressing Foil Against Wire
      G04332130Courtesy 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.

      Standard: 

      VOLTAGE CRITERIA TABLE

      Voltage Criteria
      Approx. 5 V Okay wire is not broken
      Approx. 10 V or 0 V Wire is not broken
      Fig 6: Inspecting Voltage At Center Of Heat Wire
      G04332131Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      HINT:

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

      Fig 7: Inspecting Voltage At Broken Between Center Of Wire
      G04332132Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    4. Place the voltmeter positive (+) lead against the defogger wire on the battery side.
    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.

      HINT:

      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.
      3. Thoroughly mix the repair agent (Dupont paste No. 4817).
        Fig 8: Placing Masking Tape Along Both Sides Of Wire
        G04332133Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      4. Using a fine tip brush, apply a small amount of the agent to the wire.
      5. After a few minutes, remove the masking tape.
        NOTE: Do not repair the defogger wire for at least 24 hours.
        Fig 9: Applying Small Amount Of Agent To Wire
        G04332134Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
  5. INSPECT DEFOGGER RELAY (Marking: DEF) 
    1. Inspect the continuity.

      Standard: 

      TERMINAL CONDITION SPECIFIED CONDITION TABLE

      Terminal No. Condition Specified Condition
      1 <==> 2 Constant Continuity
      3 <==> 5 Constant No continuity
      3 <==> 5 Apply B+ between terminals 1 and 2 Continuity

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

      Fig 10: Inspecting Defogger Relay Continuity
      G04332135Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
scientia non olet · About LEMON Manuals