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Home >> Lexus >> 2007 >> IS 350 >> Repair and Diagnosis >> Body & Frame >> Windows >> Windshield/Window Glass >> 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 intelligent tester to check for communication errors.

    Result 

    COMMUNICATION SYSTEM

    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 INTELLIGENT TESTER 
    1. Select the ACTIVE TEST, use the intelligent tester to issue a control command, and then check the window defogger operation.

    AIR CONDITIONER 

    AIR CONDITIONER ACTIVE TEST TABLE

    Item Test Details
    DEFOGGER RLY Turns rear window defogger OFF/ON

    Result 

    RESULT DESCRIPTION TABLE

    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 MULTIMEDIA MODULE DISPLAY 
    1. Replace the multimedia 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 INTELLIGENT TESTER 
    1. Select the ACTIVE TEST, use the intelligent tester 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 DESCRIPTION TABLE

    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 DEFOG RELAY - BATTERY POSITIVE  .

      Voltage: 

      Engine room No. 1 R/B, J/B 

      DEFOG RELAY - BATTERY POSITIVE

      Tester Connection Condition Specified Condition
      1 - Body ground Engine switch on (IG) 10 to 14 V
      Fig 1: Identifying Relay Connector Terminals
      G04050794Courtesy 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 TESTER CONNECTION SPECIFIED CONDITION TABLE  .

      Resistance 

      DEFOG RELAY - A/C AMPLIFIER ASSEMBLY

      Tester Connection Condition Specified Condition
      2 - J58-3 Always Below 1 ohms
      2 - Body ground Always 10 k ohms or higher
      Fig 2: Checking Wire Harness (Defog Relay - A/C Amplifier Assembly)
      G04050793Courtesy 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 DEFOG RELAY - BATTERY POSITIVE AND BODY GROUND  .

      Resistance: 

      Engine room No. 1 R/B, J/B 

      DEFOG RELAY - BATTERY POSITIVE AND BODY GROUND (RESISTANCE)

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

      Voltage: 

      Engine room No. 1 R/B, J/B 

      Fig 3: Identifying Relay Connector Terminals
      G04050794Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      DEFOG RELAY - BATTERY POSITIVE AND BODY GROUND (VOLTAGE)

      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 

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

      Resistance 

      NOISE FILTER

      Tester Connection Condition Specified Condition
      A1 - B1 Always Below 1 ohms
      A1 - Body ground Always 10 k ohms or higher
      Fig 4: Inspecting Noise Filter
      G04050795Courtesy 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 DEFOG RELAY - NOISE FILTER  .

      Resistance 

      DEFOG RELAY - NOISE FILTER

      Tester Connection Condition Specified Condition
      3 - Q21-1 Always Below 1 ohms
      Fig 5: Checking Wire Harness (Defog Relay - Noise Filter)
      G04050796Courtesy 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 TESTER CONNECTION SPECIFIED CONDITION TABLE  .

      Resistance 

      DEFOGGER WIRE CONNECTOR - BODY GROUND

      Tester Connection Condition Specified Condition
      P19-1 - Body ground Always Below 1 ohms
      Fig 6: Checking Wire Harness (Defogger Wire Connector - Body Ground)
      G04050797Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPAIR OR REPLACE REAR WINDOW DEFOGGER WIRE 

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