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Home >> Lexus >> 2013 >> IS 350 Base, AWD >> Repair and Diagnosis (Single Page) >> Accessories & Equipment >> Heated Glass/Defoggers >> Window Defogger System (Diagnostics & Symptom Tests) >> Window Defogger System >> Symptom Tests >> Rear Window Defogger System does not Operate >> Procedure
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Rear Window Defogger System does not Operate: Procedure

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

      Result

      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 USING TECHSTREAM 
    1. Select the Active Test, use the Techstream to issue a control command, and then check the window defogger operation.

      Air Conditioner

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

      Result

      OK (w/ Multi-display) A
      OK (w/o Multi-display) B
      NG C

    B → See step   7 

    C → See step   11 

    A: Go to next step 

  3. REPLACE MULTI-DISPLAY ASSEMBLY 
    1. Replace the multi-display assembly.

    NEXT: Go to next step 

  4. CONFIRM REAR WINDOW DEFOGGER OPERATION 
    1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

    NG → See step   5 

    OK → END 

  5. REPLACE MULTI-MEDIA MODULE RECEIVER ASSEMBLY 
    1. Replace the multi-media module receiver assembly.

    NEXT: Go to next step 

  6. 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 

  7. REPLACE INTEGRATION CONTROL AND PANEL ASSEMBLY 
    1. Replace the integration control and panel assembly.

    NEXT: Go to next step 

  8. CONFIRM REAR WINDOW DEFOGGER OPERATION 
    1. Turn the engine switch on (IG), press the defogger switch, and check that window defogger operates.

    NG → See step   9 

    OK → END 

  9. REPLACE RADIO RECEIVER ASSEMBLY 
    1. Replace the radio receiver assembly.

    NEXT: Go to next step 

  10. 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 

  11. PERFORM ACTIVE TEST USING 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

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

    OK → See step   15 

    NG: Go to next step 

  12. INSPECT DEFOG RELAY 

    Refer to ON-VEHICLE INSPECTION [08/2012 - ]

    NG → REPLACE DEFOG RELAY 

    OK: Go to next step 

  13. CHECK WIRE HARNESS (DEFOG RELAY - BATTERY POSITIVE) 
    1. Disconnect the DEFOG relay.
      GTY276331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the voltage according to the value(s) in the table below.

      Voltage

      Engine room No. 1 R/B, J/B 

      Tester Connection Condition Specified Condition
      1 - Body ground Engine switch on (IG) 10 to 14 V

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

    OK: Go to next step 

  14. 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 Condition Specified Condition
      2 - J58-3 (RDFG) Always Below 1 Ω
      2 - Body ground Always 10 kΩ or higher

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPLACE A/C AMPLIFIER ASSEMBLY 

  15. INSPECT DEFOGGER RELAY 

    Refer to ON-VEHICLE INSPECTION [08/2012 - ]

    NG → REPLACE DEFOG RELAY 

    OK: Go to next step 

  16. CHECK WIRE HARNESS (DEFOG RELAY - BATTERY POSITIVE AND BODY GROUND) 
    1. Disconnect the DEFOG relay.
      GTY276331Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    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 Condition Specified Condition
      4 - Body ground Always Below 1 Ω

      Voltage

      Engine room No. 1 R/B, J/B 

      Tester Connection Condition Specified Condition
      5 - Body ground Engine switch on (IG) 10 to 14 V

    NG → REPAIR OR REPLACE DEFOG FUSE OR HARNESS AND CONNECTOR 

    OK: Go to next step 

  17. INSPECT NOISE FILTER 
    1. Disconnect the noise filter connectors.
      GTY126047Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance according to the value(s) in the table below.

      Resistance

      Tester Connection Condition Specified Condition
      A1 - B1 Always Below 1 Ω
      A1 - Body ground Always 10 kΩ or higher

    NG → REPLACE NOISE FILTER 

    OK: Go to next step 

  18. 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 Condition Specified Condition
      3 - Q21-1 Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next step 

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

      Resistance

      Tester Connection Condition Specified Condition
      P19-1 - Body ground Always Below 1 Ω

    NG → REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK → REPAIR OR REPLACE REAR WINDOW DEFOGGER WIRE 

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