ANTI-LOCK BRAKE SYSTEM DIAGNOSIS SYSTEM


  1. DESCRIPTION

    When troubleshooting a vehicle with the diagnosis system, the only difference from the usual troubleshooting procedure is connecting the intelligent tester to the vehicle and reading various data output from the vehicle's skid control ECU.

    The skid control ECU stores DTCs when the ECU detects a malfunction in the ECU itself or in its circuits.

    To check the DTCs, connect the intelligent tester to the DLC3 of the vehicle. The intelligent tester enables you to clear the DTCs, activate various actuators, and check the Freeze Frame Data and Data List.


    1. Check the battery voltage.

      If the voltage is below 11 V, recharge the battery before proceeding to the next step.

    2. DIAGNOSIS


      1. If the skid control ECU detects a malfunction, the ABS warning light and brake warning light come on in order to warn the driver.

      2. DTCs are simultaneously stored in memory. Output DTCs can be read by connecting SST to terminals 13 (TC) and 4 (CG) of the DLC3 and observing the blinking pattern of the ABS warning light or by connecting the intelligent tester Click here.

        Note

        If parts connected to the IG terminal circuit are damaged due to high voltage, DTCs may not be able to be output from the ABS warning light and slip indicator light by connecting SST to the DLC3. In this case, inspect the IG power source circuit.

      3. This system has a test mode (signal check) function Click here.

    3. WARNING LIGHT INITIAL CHECK


      1. Release the parking brake.

        Note

        When releasing the parking brake, set chocks to prevent the vehicle from rolling.

        Tech Tips

        When the parking brake is applied or the level of the brake fluid is low, the brake warning light comes on.

      2. When the ignition switch is turned to ON, check that the ABS warning light and brake warning light come on for approximately 3 seconds.

        Tech Tips

        If the warning light check result is not normal, proceed to troubleshooting for the ABS warning light and brake warning light circuits.

        If an indicator remains on or does not come on, proceed to troubleshooting for the light circuits listed below.

      4. Trouble Area See procedure
      ABS warning light circuit (Remains on)

      Click here

      ABS warning light circuit (Does not come on)

      Click here

      Brake warning light circuit (Remains on)

      Click here

      Brake warning light circuit (Does not come on)

      Click here