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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. PERFORM ACTIVE TEST 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 / Body / Active Test.
    5. Check the operation

      Body (Main Body ECU RH) 

      ACTIVE TEST - BODY (MAIN BODY ECU RH)

      Tester Display Test Part Control Range Diagnostic Note
      Headlight Relay Headlight relay ON/OFF -

      OK: Headlight assembly (low) illuminates. 

    NG: Go to step 2 

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

  2. INSPECT FUSE (H-LP L LWR, H-LP R LWR) 
    1. Remove the H-LP L LWR fuse from the No 2 engine room relay block.
    2. Remove the H-LP R LWR fuse from the No 2 engine room relay block
    3. Measure the resistance of the fuses.

      Standard Resistance: 

      Below 1 Ω 

    NG: REPLACE FUSE 

    OK: Go to next Step 

  3. INSPECT HEAD LP RELAY 
    1. Remove the HEAD LP relay from the engine room No 1 relay block
    2. Measure the resistance according to the value (s) in the table below

      Standard Resistance 

      STANDARD RESISTANCE SPECIFICATION

      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)
      3. Fig 1: Identifying Head LP Relay Terminal
      G05298808Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE HEAD LP RELAY 

    OK: Go to next Step 

  4. CHECK HARNESS AND CONNECTOR (MAIN BODY ECU RH - BATTERY) 
    1. Disconnect the RL main body ECU RH connector
    2. Measure the voltage according to the value (s) in the table below

      Standard Voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      RL-7 (HRLY) - Body ground Always 11 to 14 V
      3. Fig 2: Identifying RL Main Body ECU RH Connector Terminal
      G05756420Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

    OK: Go to next Step 

  5. CHECK HARNESS AND CONNECTOR (HEADLIGHT (LOW LH OR LOW RH) - BATTERY AND BODY GROUND) 
    1. Check the wire harness between the headlight (Low LH) and battery, and the headlight (Low LH) and body ground
      1. Disconnect the B12 headlight connector.
      2. Measure the voltage according to the value (s) in the table below.

        Standard Voltage 

        STANDARD VOLTAGE SPECIFICATION

        Tester Connection Condition Specified Condition
        B12-17 (LO) - Body ground Turn the light control switch to the ON (HEAD) position. 11 to 14 V
      3. Measure the resistance according to the value (s) in the table below

        Standard Resistance 

        STANDARD RESISTANCE SPECIFICATION

        Tester Connection Condition Specified Condition
        B12-16 (E) - Body ground Always Below 1 Ω
        Fig 3: Identifying Headlight Assembly Connector Terminal B12
        G05756421Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the wire harness between the headlight (Low RH) and battery, and the headlight (Low RH) and body ground.
      1. Disconnect the B2 headlight connector.
      2. Measure the voltage according to the value (s) in the table below.

        Standard Voltage 

        STANDARD VOLTAGE SPECIFICATION

        Tester Connection Condition Specified Condition
        B2-17 (LO) - Body ground Turn the light control switch to the ON (HEAD) position. 11 to 14 V
      3. Measure the resistance according to the value (s) in the table below

        Standard Resistance 

        STANDARD RESISTANCE SPECIFICATION

        Tester Connection Condition Specified Condition
        B2-16 (E) - Body ground Always Below 1 Ω
      3. Fig 4: Identifying B2 Headlight Connector
      G05756422Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: Go to step 6 

    OK: REPLACE HEADLIGHT ASSEMBLY (LOW LH OR LOW RH)  (See HEADLIGHT ASSEMBLY  )

  6. CHECK HARNESS AND CONNECTOR (HEADLIGHT (LOW LH OR LOW RH) - HEAD LP RELAY) 
    1. Check the harness and the connectors between the headlight (Low LH or Low RH) and the HEAD LP relay
      1. Disconnect the B12 headlight connector
      2. Remove the HEAD LP relay from the engine room No. 1 relay block
      3. Measure the resistance according to the value (s) in the table below

        Standard Resistance (Check for Open) 

        STANDARD RESISTANCE SPECIFICATION

        Headlight Assembly Tester Connection Specified Condition
        LH B12-17 (LO) - HEAD LP relay terminal (3) Below 1 Ω
        RH B2-17 (LO) - HEAD LP relay terminal (3) Below 1 Ω

        Standard Resistance (Check for Short) 

        STANDARD RESISTANCE SPECIFICATION

        Headlight Assembly Tester Connection Specified Condition
        LH B12-17 (LO) or HEAD LP relay terminal (3) - Body ground 10 kΩ or higher
        RH B2-17 (LO) or HEAD LP relay terminal (3) - Body ground 10 kΩ or higher
      2. Fig 5: Identifying Head LP Relay Terminal
      G05756423Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS OR CONNECTOR 

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

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