2007 Lexus SC 430FACTORY OEM SERVICE PROCEDURE

Inspection Procedure

  1. PERFORM ACTIVE TEST BY INTELLIGENT TESTER (REAR WINDOW DEFOGGER WIRE) 
    1. Select the ACTIVE TEST, use the intelligent tester to generate a control command, and then check the rear window defogger wire.

      Luggage room junction block ECU 

      ITEM CONTENT REFERENCE CHART

      Item Test Details Diagnostic Note
      DEFOGGER RLY-R Operate rear window defogger wire ON/OFF -

      OK: Rear window defogger wire operates. 

    OK: REPLACE LUGGAGE ROOM JUNCTION BLOCK ASSEMBLY (LUGGAGE ROOM JUNCTION BLOCK ECU) 

    NG: Go to Next Step 

  2. INSPECT FUSE (DEFOG) 
    1. Remove the DEFOG M-fuse from the luggage room junction block.
    2. Measure the resistance of the fuse.

      Standard resistance: Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to Next Step 

  3. INSPECT DEFOGGER RELAY (Marking: DEFOG) 
    1. Remove the DEFOG relay from the luggage room junction block.
    2. Measure the resistance of the relay.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      3 - 5 10 kΩ or higher
      3 - 5 Below 1 Ω (when battery voltage is applied to terminals 1 and 2)
      Fig 1: Identifying Defogger Relay Terminals
      G05293509Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE DEFOG RELAY 

    OK: Go to Next Step 

  4. CHECK WIRE HARNESS (LUGGAGE ROOM JUNCTION BLOCK - BATTERY) 
    1. Disconnect the 6L junction block connector.
    2. Measure the voltage of the wire harness side connector.
      Fig 2: Identifying Wire Harness Side
      G05293510Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

      Standard voltage 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      6L-1 - Body ground 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  5. CHECK WIRE HARNESS (LUGGAGE ROOM JUNCTION BLOCK - REAR WINDOW DEFOGGER WIRE) 
    Fig 3: Identifying Luggage Room Junction Block Connector Terminals And Rear Window Defogger Wire Connector Terminals
    G05293511Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Disconnect the 6D junction block connector.
    2. Disconnect the R12 defogger connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      6D-1 - R12-1 Below 1 Ω
      6D-1 or R12-1 - Body ground 10 kΩ or higher

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  6. CHECK WIRE HARNESS (REAR WINDOW DEFOGGER WIRE - BODY GROUND) 
    1. Disconnect the R13 defogger connector.
      Fig 4: Identifying R13 Defogger Connector Terminals
      G05293512Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Measure the resistance of the wire harness side connector.

      Standard resistance 

      TESTER CONNECTION SPECIFIED CONDITION

      Tester Connection Specified Condition
      R13-1 - Body ground Below 1 Ω

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to Next Step 

  7. INSPECT REAR WINDOW DEFOGGER WIRE 
    NOTE:
    • When cleaning the glass, wipe the glass along the wire using a soft and dry cloth. Take care not to damage the wires.
    • Do not use detergents or glass cleaners that have abrasive ingredients.
    • When measuring voltage, wrap a piece of tin foil around the tip of the negative tester probe and press the foil against the wire with your finger, as shown in the illustration.
      Fig 5: Inspecting Rear Window Defogger Wire
      G05293513Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    1. Turn the ignition switch ON.
    2. Turn the defogger switch ON.
    3. Measure the voltage at the center of each defogger wire as shown in the illustration.

      Standard voltage 

      STANDARD VOLTAGE REFERENCE CHART

      Voltage Criteria
      Approx. 5 V Wire is not broken
      Approx. 10 or 0 V Wire is broken

      HINT:

      If there is approximately 10 V, the wire may be faulty between the center of the wire and the wire end on the battery side. If there is no voltage, the wire may be faulty between the center of the wire and the wire end on the ground side.

      Fig 6: Measuring Voltage Center Of Defogger Wire
      G05293514Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
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