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ABS Warning Light Remains ON [03/2017 - ]: Procedure

  1. CHECK CAN COMMUNICATION SYSTEM 
    1. Check if CAN communication system DTCs are output.

      Refer to DIAGNOSIS SYSTEM [03/2017 - 06/2019] , or refer to DIAGNOSIS SYSTEM [06/2019 - 04/2020] , or refer to DIAGNOSIS SYSTEM [04/2020 - 11/2021] , or refer to DIAGNOSIS SYSTEM [11/2021 - 10/2022] , or refer to DIAGNOSIS SYSTEM [10/2022 - 05/2023] , or refer to DIAGNOSIS SYSTEM [05/2023 - ]

      Result

      Result Proceed to
      DTCs are not output. A
      DTCs are output. B

    Result: 

    INSPECT CAN COMMUNICATION SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2017 - 09/2018]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [09/2018 - 05/2023]  , or refer to  HOW TO PROCEED WITH TROUBLESHOOTING [05/2023 - ] 

    Result: 

    See step  2

  2. CHECK IF SKID CONTROL ECU ASSEMBLY CONNECTOR IS SECURELY CONNECTED 
    1. Check if the skid control ECU assembly connector is securely connected.

      OK

      The connector is securely connected.

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CONNECT CONNECTOR TO SKID CONTROL ECU ASSEMBLY CORRECTLY 

    Result: 

    OK 

    See step  3

  3. CHECK BATTERY 
    1. Check the battery voltage.

      Standard Voltage

      Tester Connection Condition Specified Condition
      Battery Engine switch off 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    CHARGE OR REPLACE BATTERY 

    Result: 

    OK 

    See step  4

  4. CHECK HARNESS AND CONNECTOR (IG1 TERMINAL) 
    1. Disconnect the A9 skid control ECU assembly connector.
      GTY789535Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU Assembly)
    2. Turn the engine switch on (IG).
    3. Measure the voltage according to the value(s) in the table below.

      Standard Voltage

      Tester Connection Condition Specified Condition
      A9-2 (IG1) - Body ground Engine switch on (IG) 11 to 14 V

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (IG1 CIRCUIT) 

    Result: 

    OK 

    See step  5

  5. CHECK HARNESS AND CONNECTOR (GND TERMINAL) 
    1. Turn the engine switch off.
      GTY786853Courtesy of © TOYOTA, LICENSE AGREEMENT TMS1002
      *a Front view of wire harness connector
      (to Skid Control ECU Assembly)
      - -
    2. Disconnect the A11, A8 and A10 skid control ECU assembly connectors.
    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance

      Tester Connection Condition Specified Condition
      A8-1 (GND) - Body ground Always Below 1 Ω
      A9-3 (GND2) - Body ground Always Below 1 Ω
      A9-1 (GND3) - Body ground Always Below 1 Ω
      A10-3 (GND4) - Body ground Always Below 1 Ω
      A10-1 (GND5) - Body ground Always Below 1 Ω
      A11-3 (GND6) - Body ground Always Below 1 Ω

      Result

      Proceed to
      OK
      NG

    Result: 

    NG 

    REPAIR OR REPLACE HARNESS OR CONNECTOR (GND CIRCUIT) 

    Result: 

    OK 

    See step  6

  6. READ VALUE USING TECHSTREAM (ABS WARNING LIGHT) 
    1. Reconnect the A9, A11, A8 and A10 skid control ECU assembly connectors.
    2. Connect the Techstream to the DLC3.
    3. Turn the engine switch on (IG).
    4. Select the Data List on the Techstream.

      Refer to DATA LIST / ACTIVE TEST [03/2017 - 05/2023] , or refer to DATA LIST / ACTIVE TEST [05/2023 - ]

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display Measurement Item Range Normal Condition Diagnostic Note
      ABS Warning Light ABS warning light ON or OFF ON: Warning light on
      OFF: Warning light off
      -

      Chassis > ABS/VSC/TRAC > Data List 

      Tester Display
      ABS Warning Light
    5. Check the Techstream display condition of the ABS warning light.

      Result

      Result Proceed to
      OFF is displayed. A
      ON is displayed. B

    Result: 

    INSPECT METER / GAUGE SYSTEM. Refer to  HOW TO PROCEED WITH TROUBLESHOOTING [03/2017 - ] 

    Result: 

    REPLACE SKID CONTROL ECU ASSEMBLY. Refer to  REMOVAL [03/2017 - 05/2023]  , or refer to  REMOVAL [05/2023 - ]