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Home >> Lexus >> 2008 >> IS 350 >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/WINDOWGLASS >> Window Defogger System >> Rear Window Defogger System does not Operate >> Inspection Procedure
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Inspection Procedure

  1. CHECK COMMUNICATION SYSTEM 
    1. Select the DTC check on the Techstream to check for communication errors.

      Result 

      RESULT CHART

      Not output DTC codes A
      Output DTC codes (Multiplex communication) B
      Output DTC codes (CAN communication) C

    B:  GO TO MULTIPLEX COMMUNICATION SYSTEM

    C:  GO TO CAN COMMUNICATION SYSTEM

    A: Go to Next Step 

  2. PERFORM ACTIVE TEST BY TECHSTREAM 
    1. Select the Active Test, use the Techstream to issue a control command, and then check the window defogger operation.

      Air Conditioner 

      ACTIVE TEST CHART

      Tester Display Test Part Control Range Diagnostic Note
      Defogger Rly-R Turns rear window defogger OFF/ON -

      Result 

      RESULT CHART

      OK (with Navigation System) A
      OK (without Navigation System) B
      NG C

    B:  Go to step  5

    C:  Go to step  9

    A: Go to Next Step 

  3. REPLACE MULTI-MEDIA MODULE DISPLAY 
    1. Replace the multi-media module display.
  4. CONFIRM REAR WINDOW DEFOGGER OPERATION 
    1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

    NG: REPLACE A/C AMPLIFIER ASSEMBLY 

    OK: END 

  5. REPLACE INTEGRATION CONTROL & PANEL 
    1. Replace the integration control & panel.
  6. CONFIRM REAR WINDOW DEFOGGER OPERATION 
    1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

    OK: END 

    NG: Go to Next Step 

  7. REPLACE RADIO RECEIVER ASSEMBLY 
    1. Replace the radio receiver assembly.
  8. REAR WINDOW DEFOGGER OPERATION 
    1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

    NG: REPLACE A/C AMPLIFIER ASSEMBLY 

    OK: END 

  9. PERFORM ACTIVE TEST BY TECHSTREAM 
    1. Select the Active Test, use the Techstream to issue a control command, and then check the DEFOG relay operation.
    2. Check that operation sound of the DEFOG relay is heard.

      Result 

      RESULT CHART

      Relay operating sound Is heard OK
      Relay operating sound is not heard NG

    OK:  Go to step  13

    NG: Go to Next Step 

  10. INSPECT DEFOG RELAY 

    See ON-VEHICLE INSPECTION 

    NG: REPLACE DEFOG RELAY 

    OK: Go to Next Step 

  11. CHECK WIRE HARNESS (DEFOG RELAY - BATTERY POSITIVE) 
    1. Disconnect the DEFOG relay.
    2. Measure the voltage according to the value (s) in the table below.

      Voltage: 

      Engine room No. 1 R/B, J/B 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      1 - Body ground Engine switch on (IG) 10 to 14 V
      3. Fig 1: Identifying DEFOG Relay Terminals
      G05828374Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE LH-IG FUSE OR HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  12. CHECK WIRE HARNESS (DEFOG RELAY - A/C AMPLIFIER ASSEMBLY) 
    1. Disconnect the DEFOG relay and A/C amplifier assembly connector.
    2. Measure the resistance according to the value (s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      2 - J58-3 Always Below 1 Ω
      2 - Body ground Always 10 kΩ or higher
      3. Fig 2: Identifying DEFOG Relay And A/C Amplifier Assembly Connector Terminals
      G05832918Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE A/C AMPLIFIER ASSEMBLY 

  13. INSPECT DEFOGGER RELAY 

    See ON-VEHICLE INSPECTION 

    NG: REPLACE DEFOG RELAY 

    OK: Go to Next Step 

  14. CHECK WIRE HARNESS (DEFOG RELAY - BATTERY POSITIVE AND BODY GROUND) 
    1. Disconnect the DEFOG relay.
    2. Measure the voltage and resistance according to the value (s) in the table below.

      Resistance: 

      Engine room No. 1 R/B, J/B 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      4 - Body ground Always Below 1 Ω

      Voltage: 

      Engine room No. 1 R/B, J/B 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      5 - Body ground Engine switch on (IG) 10 to 14 V
      Fig 3: Identifying DEFOG Relay Terminals
      G05828374Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE DEFOG FUSE OR HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  15. INSPECT NOISE FILTER 
    1. Disconnect the noise filter connectors.
    2. Measure the resistance according to the value (s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      A - B1 Always Below 1 Ω
      A1 - Body ground Always 10 kΩ or higher
      3. Fig 4: Identifying Noise Filter Connector Terminals
      G05832920Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE NOISE FILTER 

    OK: Go to Next Step 

  16. CHECK WIRE HARNESS (DEFOG RELAY - NOISE FILTER) 
    1. Disconnect the DEFOG relay and defogger wire connectors.
    2. Measure the resistance according to the value (s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      3 - Q21-1 Always Below 1 Ω
      3. Fig 5: Identifying DEFOG Relay And Q21 Connector Terminals
      G05832921Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to Next Step 

  17. CHECK WIRE HARNESS (DEFOGGER WIRE CONNECTOR - BODY GROUND) 
    1. Measure the resistance according to the value (s) in the table below.

      Resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Condition Specified Condition
      P19-1 - Body ground Always Below 1 Ω
      2. Fig 6: Identifying P19 Connector
      G05832922Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE REAR WINDOW DEFOGGER WIRE 

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