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Home >> Lexus >> 2008 >> LX 570 >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/WINDOWGLASS >> Windshield Deicer System >> Windshield Deicer does not Operate >> Inspection Procedure
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Inspection Procedure

  1. CHECK FOR DTC 
    1. Check for DTC.

      OK: DTC is not output. 

    NG: GO TO CAN COMMUNICATION SYSTEM  (See DIAGNOSTIC TROUBLE CODE CHART )

    OK: Go to next step 

  2. PERFORM ACTIVE TEST USING TECHSTREAM (DEICER RELAY) 
    1. Select the Active Test using the Techstream to generate a control command, and then check that the windshield deicer operates.

      Air Conditioner 

      AIR CONDITIONER REFERENCE

      Tester Display Test Part Control Range Diagnostic Note
      Deicer Relay (Front) Deicer relay operation OFF or ON -

      Result 

      RESULT REFERENCE

      Result Proceed to
      Windshield deicer operates normally (w/ Navigation System) A
      Windshield deicer operates normally (w/ o Navigation System) B
      Windshield deicer does not operate C

    B:  Go to step  5

    C:  Go to step  7

    A: Go to next step 

  3. REPLACE DISPLAY AND NAVIGATION MODULE DISPLAY 
    1. Temporarily replace the display and navigation module display with a new or normally functioning one (See REMOVAL ).
  4. CHECK WINDSHIELD DEICER SYSTEM 
    1. Turn the engine switch on (IG).
    2. Check that pressing the windshield deicer switch illuminates the indicator and warms the front windshield surface.
    3. Check that after approximately 15 minutes, the indicator light turns off and the windshield deicer deactivates.

      OK: Windshield deicer system functioning normally. 

    NG: REPLACE AIR CONDITIONING AMPLIFIER  (See REMOVAL )

    OK: END 

  5. REPLACE MULTI-DISPLAY 
    1. Temporarily replace the multi-display with a new or normally functioning one (See REMOVAL ).
  6. CHECK WINDSHIELD DEICER SYSTEM 
    1. Turn the engine switch on (IG).
    2. Check that pressing the windshield deicer switch illuminates the indicator and warms the front windshield surface.
    3. Check that after approximately 15 minutes, the indicator light turns off and the windshield deicer deactivates.

      OK: Windshield deicer system functioning normally. 

    NG: REPLACE AIR CONDITIONING AMPLIFIER  (See REMOVAL )

    OK: END 

  7. CHECK FUSE (DEICER) 
    1. Remove the DEICER fuse from the engine room junction block.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      DEICER fuse Always Below 1 Ω

    NG: REPLACE FUSE 

    OK: Go to next step 

  8. INSPECT DEICER RELAY 
    1. Remove the deicer relay from the engine room relay block.
    2. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      3 - 5 Battery voltage is not applied to terminals 1 and 2 10 kΩ or higher
      Battery voltage is applied to terminals 1 and 2 Below 1 Ω
      Fig 1: Identifying Engine Room Relay Terminals
      G05636437Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE DEICER RELAY 

    OK: Go to next step 

  9. CHECK HARNESS AND CONNECTOR (DEICER RELAY - AIR CONDITIONING AMPLIFIER AND BATTERY) 
    1. Remove the deicer relay from the engine room relay block.
    2. Disconnect the E36 air conditioning amplifier connector.
    3. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      Deicer relay terminal 2 - Body ground Engine switch on (IG) 11 to 14 V
      Deicer relay terminal 5 - Body ground Always 11 to 14 V
    4. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      Deicer relay terminal 1 - E36-23 (FDEF) Always Below 1 Ω
      Deicer relay terminal 1 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 2: Identifying E36 Connector Terminal
    G05767556Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  10. CHECK HARNESS AND CONNECTOR (DEICER RELAY - WINDSHIELD DEICER WIRE) 
    1. Remove the deicer relay from the engine room relay block.
    2. Disconnect the A23 windshield deicer wire connector.
    3. Measure the resistance according to the value (s) in the table below.

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      A23-1 (B) - Deicer relay terminal 3 Always Below 1 Ω
      Deicer relay terminal 3 - Body ground Always 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 3: Identifying Engine Room Relay Block And A23 Connector Terminal
    G05767557Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  11. CHECK HARNESS AND CONNECTOR (WINDSHIELD DEICER WIRE - BODY GROUND) 
    1. Disconnect the A23 windshield deicer wire connector
    2. Measure the resistance according to the value (s) in the table below

      Standard Resistance 

      RESISTANCE REFERENCE

      Tester Connection Condition Specified Condition
      A23-2 (E) - Body ground Always Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    Fig 4: Identifying A23 Connector Terminal
    G05767558Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  12. CHECK WINDSHIELD DEICER WIRE 
    1. Disconnect the A23 windshield deicer wire connector.
    2. Measure the voltage according to the value (s) in the table below.

      Standard Voltage 

      VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      A23-1 (B) - A23-2 (E) Engine switch on (IG) and deicer switch on 11 to 14 V

    NG: REPLACE AIR CONDITIONING AMPLIFIER  (See REMOVAL )

    Fig 5: Identifying A23 Connector Terminal
    G05767559Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: REPLACE WINDSHIELD GLASS  (See REMOVAL  )

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