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Inspection Procedure

  1. CHECK WIRE HARNESS (HEADLIGHT BEAM LEVEL CONTROL ECU - COWL SIDE JUNCTION BLOCK ECU LH) 
    1. Disconnect the A43 headlight beam level control ECU connector.
    2. Disconnect the A30 cowl side junction block ECU connector.
    3. Measure the resistance of the wire harness side connectors.

      Standard resistance 

      RESISTANCE SPECIFICATION

      Tester Connection Specified Condition
      A43-8 (CHG-) - A30-13 (ALTL) Below 1 Ω
      A43-26 (WNG) - A30-14 (WNG) Below 1 Ω
      A43-8 (CHG-) or A30-13 (ALTL) - Body ground 10 kΩ or higher
      A43-26 (WNG) or A30-14 (WNG) - Body ground 10 kΩ or higher
    Fig 1: Identifying A43 Headlight Beam Level Control And A30 Cowl Side Junction Block ECU Connector
    G05298903Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  2. CHECK WIRE HARNESS (HEADLIGHT BEAM LEVEL CONTROL ECU - SKID CONTROL ECU WITH ACTUATOR OR SKID CONTROL ECU) 
    1. Check the wire harness between the headlight beam level control ECU and skid control ECU with actuator (3GR-FSE).
      1. Disconnect the A43 headlight beam level control ECU connector.
      2. Disconnect the A44 skid control ECU with actuator connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        A43-6 (SPDR) - A44-37 (FRO) Below 1 Ω
        A43-5 (SPDL) - A44-38 (FLO) Below 1 Ω
        A43-6 (SPDR) or A44-37 (FRO) - Body ground 10 kΩ or higher
        A43-5 (SPDL) or A44-38 (FLO) - Body ground 10 kΩ or higher
      Fig 2: Identifying A43 Headlight Beam Level Control And A44 Skid Control ECU With Actuator Connector
      G05298904Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
    2. Check the wire harness between the headlight beam level control ECU and skid control ECU (3UZ-FE).
      1. Disconnect the A43 headlight beam level control ECU connector.
      2. Disconnect the A13 and A15 skid control ECU connector.
      3. Measure the resistance of the wire harness side connectors.

        Standard resistance 

        RESISTANCE SPECIFICATION

        Tester Connection Specified Condition
        A43-6 (SPDR) - A13-10 (FRO) Below 1 Ω
        A43-5 (SPDL) - A15-10 (FLO) Below 1 Ω
        A43-6 (SPDR) or A13-10 (FRO) - Body ground 10 kΩ or higher
        A43-5 (SPDL) or A15-10 (FLO) - Body ground 10 kΩ or higher
    Fig 3: Identifying A43 Headlight Beam Level And A13 And A15 Skid Control ECU Connector
    G05298905Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

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

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