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Inspection Procedure

WARNING: This page is about a different car, the 2008 Lexus IS F. However, it is still accessible from the selected car via links, so may be relevant.
  1. READ VALUE USING TECHSTREAM 
    1. Connect the Techstream to the DLC3.
    2. Turn the engine switch on (IG).
    3. Turn the Techstream on.
    4. Enter the following menus. Body Electrical / (desired system) / Data List.
    5. Read the display on the Techstream.

      Body (Main Body ECU RH) 

      DIAGNOSTIC NOTE

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Illumination SW Front interior light switch (marked ON/OFF) signal / ON or OFF ON Front interior light switch (marked ON/OFF) is pushed in
      OFF Front interior light switch (marked ON/OFF) is not pushed in      		 -

      Body No. 3 (Main Body ECU LH) 

      DIAGNOSTIC NOTE

      Tester Display Measurement Item/Range Normal Condition Diagnostic Note
      Interior Light Front interior light switch (marked DOOR) signal / ON or OFF ON Front interior light switch (marked ON/OFF) is pushed in
      OFF Front interior light switch (marked ON/OFF) is not pushed in      		 -

      OK: Switch condition can be displayed. 

      Result 

      RESULT CHART

      Result Proceed to
      Indication for "Illumination SW" does not change A
      Indication for "Interior Light" does not change B
      Indications for both "Illumination SW" and "Interior Light" do not change C
      OK D

    A: Go to step 2 

    B: Go to step  4

    C: Go to step  6

    D: PROCEED TO NEXT CIRCUIT INSPECTION SHOWN IN PROBLEM SYMPTOMS TABLE  (See PROBLEM SYMPTOMS TABLE  )

  2. INSPECT OVERHEAD JUNCTION BLOCK 
    1. Remove the overhead junction block.
    2. Measure the resistance according to the value(s) in the table.

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is not pushed In 10 kΩ or higher
      R5-34 (CILL) - RS-18 (GND3) Front interior light switch (marked ON/OFF) is pushed in Approx. 10 Ω
      3. Fig 1: Identifying Overhead Junction Block
      G05754620Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE OVERHEAD JUNCTION BLOCK  (See PERSONAL LIGHT  )

    OK: Go to next step 

  3. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MAIN BODY ECU RH) 
    1. Disconnect the R5 overhead junction block connector
    2. Disconnect the J75 main body ECU RH connector.
    3. Measure the resistance according to the value(s) in the table

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R5-34 (CILL) - J75-4 (UL2) Always Below 1 Ω
      RS-34 (CILL) - Body ground Always 10 kΩ or higher
      4. Fig 2: Identifying Harness And Connector (Overhead Junction Block - Main Body ECU RH)
      G05754621Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU RH (COWL SIDE JUNCTION BLOCK RH) 

  4. INSPECT OVERHEAD JUNCTION BLOCK 
    1. Remove the overhead junction block
    2. Measure the resistance according to the value(s) in the table

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is not pushed in 10 kΩ or higher
      R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is pushed in Approx 10 Ω
      3. Fig 3: Identifying Overhead Junction Block
      G05754622Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE OVERHEAD JUNCTION BLOCK  (See PERSONAL LIGHT  )

    OK: Go to next step 

  5. CHECK HARNESS AND CONNECTOR (OVERHEAD JUNCTION BLOCK - MAIN BODY ECU LH) 
    1. Disconnect the R5 overhead junction block connector.
    2. Disconnect the Q3 main body ECU LH connector.
    3. Measure the resistance according to the value(s) in the table

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Condition Specified Condition
      R5-35 (DOOR) - Q3-11 (BDCY) Always Below 1 Ω
      R5-35 (DOOR) - Body ground Always 10 kΩ or higher
      4. Fig 4: Identifying Harness And Connector (Overhead Junction Block - Main Body ECU LH)
      G05754623Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: REPLACE MAIN BODY ECU LH (COWL SIDE JUNCTION BLOCK LH) 

  6. INSPECT OVERHEAD JUNCTION BLOCK 
    1. Remove the overhead junction block.
    2. Measure the resistance according to the value(s) in the table

      Standard Resistance 

      TESTER CONNECTION SPECIFIED CONDITION CHART

      Tester Connection Switch Condition Specified Condition
      R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is not pushed in 10 kΩ or higher
      R5-35 (DOOR) - R5-18 (GND3) Front interior light switch (marked DOOR) is pushed in Approx. 10 Ω
      R5-34 (CILL) - RS-18 (GND3) Front interior light switch (marked ON/OFF) is not pushed in 10 kΩ or higher
      R5-34 (CILL) - R5-18 (GND3) Front interior light switch (marked ON/OFF) is pushed in Approx. 10 Ω
      Fig 5: Identifying Overhead Junction Block
      G05754624Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE OVERHEAD JUNCTION BLOCK  (See PERSONAL LIGHT  )

    OK: REPAIR OR REPLACE HARNESS OR CONNECTOR (OVERHEAD JUNCTION BLOCK GROUND CIRCUIT) 

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