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Inspection Procedure

  1. INSPECT FUSE (ABS MAIN3) 
    1. Remove the ABS MAIN3 fuse from the engine room relay block.
    2. Measure the resistance of the fuse.

      Standard resistance: 

      Below 1 Ω 

    NG: CHECK FOR SHORT IN ALL HARNESS AND CONNECTOR CONNECTED TO FUSE AND REPLACE FUSE 

    Fig 1: Inspecting Fuse (ABS MAIN3)
    G05189303Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  2. CHECK BRAKE CONTROL POWER SUPPLY (BC VOLTAGE) 
    1. Measure the voltage of the connector.

      HINT:

      Measure the voltage from behind the connector with the connector connected.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      B18-8 (BC) - Body ground 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 2: Identifying Brake Control Power Supply B18 Connector
    G05189304Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  3. CHECK SKID CONTROL ECU (+BI1, +BI2 VOLTAGE) 
    1. Measure the voltage of the connectors.

      HINT:

      Measure the voltage from behind the connector with the connector connected to the skid control ECU.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      S8-3 (+B11) - Body ground 10 to 14 V
      S9-5 (+BI2) - Body ground 10 to 14 V
      Fig 3: Checking Skid Control ECU (+BI1, +BI2 Voltage)
      G05189305Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    OK: Go to next step 

  4. CHECK SKID CONTROL ECU (+BO1, +BO2 VOLTAGE) 
    1. Measure the voltage of the connectors.

      HINT:

      Measure the voltage from behind the connector with the connector connected to the skid control ECU.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Specified Condition
      S8-5 (+BO1) - Body ground 10 to 14 V
      S9-4 (+BO2) - Body ground 10 to 14 V

    NG: REPAIR OR REPLACE HARNESS AND CONNECTOR 

    Fig 4: Identifying S8 And S9 Connector Terminal
    G05189306Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    OK: Go to next step 

  5. CHECK BRAKE CONTROL POWER SUPPLY (OUT, BCTY, OUT2 VOLTAGE) 
    1. Measure the voltage of the connector.

      HINT:

      Measure the voltage from behind the connector with the connector connected.

      Standard voltage 

      STANDARD VOLTAGE SPECIFICATION

      Tester Connection Condition Specified Condition
      B18-1 (OUT) - Body ground Power switch ON (READY) 9 to 13 V
      B18-2 (BCTY) - Body ground Power switch ON (READY) 9 to 13 V
      B18-7 (OUT2) - Body ground Power switch ON (READY) 9 to 13 V
      Fig 5: Checking Brake Control Power Supply (OUT1, BCTY, OUT2 Voltage)
      G05189307Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002

    NG: REPLACE BRAKE CONTROL POWER SUPPLY 

    OK: REPAIR OR REPLACE HARNESS AND CONNECTOR