ELECTRONICALLY CONTROLLED 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 GTS to the vehicle and reading various data output from the vehicle's skid control ECU assembly.

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

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


    1. Check the auxiliary battery voltage.

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

    2. Check the DLC3 Click here.

    3. DIAGNOSIS


      1. If the skid control ECU assembly detects a malfunction, the ABS warning, brake warning / red (malfunction), brake warning / yellow (minor malfunction) and slip indicator lights will come on in order to warn the driver. Also, when the brake hold switch is turned on, the brake hold operated indicator light blinks.

      2. The DTCs are simultaneously stored in the memory.

        The DTCs can be read by connecting SST between terminals TC and CG of the DLC3 and observing the blinking pattern of the ABS warning, brake warning / yellow (minor malfunction), slip indicator and brake hold standby indicator lights, or by connecting the GTS Click here.

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

        The DTCs can be read by connecting SST between terminals TS and CG of the DLC3 and observing the blinking pattern of the ABS warning, brake warning / yellow (minor malfunction) and slip indicator lights, or by connecting the GTS Click here.

    4. WARNING LIGHT AND INDICATOR LIGHT INITIAL CHECK


      1. When the power switch is turned on (IG), check that the VSC OFF indicator light comes on for approximately 3 seconds, and ABS warning, brake warning / red (malfunction), brake warning / yellow (minor malfunction), slip indicator, brake hold standby indicator and brake hold operated indicator lights remain on until the power switch is turned on (READY).

        Tech Tips


        • If the warning light and indicator light check result is not normal, proceed to troubleshooting for the ABS warning, brake warning / red (malfunction), brake warning / yellow (minor malfunction), VSC OFF indicator, slip indicator, brake hold standby indicator and brake hold operated indicator light circuits.

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

      5. 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 / red (malfunction) circuit (Remains on)

      Click here

      Brake warning light / red (malfunction) circuit (Does not come on)

      Click here

      Brake warning light / yellow (minor malfunction) circuit (Remains on)

      Click here

      Brake warning light / yellow (minor malfunction) circuit (Does not come on)

      Click here

      VSC OFF indicator light circuit (Remains on)

      Click here

      VSC OFF indicator light circuit (Does not come on)

      Click here

      Slip indicator light circuit (Remains on)

      Click here

      Slip indicator light circuit (Does not come on)

      Click here

      Brake hold standby indicator light circuit

      Click here

      Brake hold operated indicator light circuit

      Click here