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 (brake actuator assembly).

    The skid control ECU (brake actuator assembly) records DTCs when the computer detects a malfunction in the computer itself or in its circuits.

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


    1. Check the battery voltage.

      If the voltage is below 20 V, recharge the battery before proceeding to the next step.

    2. Replace the normal DLC3 cable (12 V specification) for the intelligent tester with the 24 V DLC3 cable.

      Note

      Be sure to use the 24 V DLC3 cable when connecting the intelligent tester to the DLC3. Using the normal DLC3 cable (12 V specification) will cause damage to the tester.

    3. Check the DLC3 Click here.

    4. DIAGNOSIS


      1. If the skid control ECU (brake actuator assembly) detects a malfunction, the ABS warning and brake warning will blink in order to warn the driver.

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

      3. This system has a Test Mode (signal check) function Click here.

    5. WARNING LIGHT INITIAL CHECK


      1. Release the parking brake.

        Note

        Before 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 and brake warning lights come on for approximately 3 seconds.

        Tech Tips

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

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

      6. 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