Diagnosis System [02/2019 - 12/2021]

When troubleshooting a vehicle with a diagnosis system, the only difference from the usual troubleshooting procedure is connecting the Techstream to the vehicle and reading various data output from the skid control ECU (brake booster with master cylinder assembly).

The skid control ECU (brake booster with master cylinder assembly) records DTCs when it detects a malfunction in itself or in its circuits.

To check for DTCs, connect the Techstream to the DLC3 on the vehicle. The Techstream can be used to clear the DTCs, activate various actuators, and check the Freeze Frame Data and Data List.

1. Check the auxiliary battery voltage.

   Standard voltage

   11 to 14 V

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

2. Check the DLC3.

   Refer to GENERAL INFORMATION [11/2018 - ]

1. If the skid control ECU (brake booster with master cylinder 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, if the vehicle is under the following conditions and the brake hold switch (integration control and panel assembly) is turned on, the brake hold operated indicator light blinks.
   1. Vehicle Conditions:
      1. The driver's door is closed.
      2. Driver's seat belt is fastened.
2. DTCs are simultaneously stored in memory.

   The DTCs can be read by connecting the Techstream.

   Refer to DTC CHECK / CLEAR [02/2019 - 12/2021] 

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

   The DTCs can be read by connecting the Techstream.

   Refer to TEST MODE PROCEDURE [02/2019 - 08/2020] , or refer to TEST MODE PROCEDURE [08/2020 - 12/2021] 

1. When the ignition switch is turned to ON, 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 come on until the ignition switch is turned to ON (READY).

   HINT: 

   • When the brake fluid level is low, the brake warning light / red (malfunction) comes on.
   • If the warning light and indicator light check results are not normal, proceed to troubleshooting for the ABS warning, brake warning / red (malfunction), brake warning / yellow (minor malfunction), slip indicator, brake hold standby indicator and brake hold operated indicator light circuits.
   • If an indicator remains on or does not come on, proceed to troubleshooting for the light circuits listed below.

   Trouble Area	See Procedure
   ABS warning light circuit (Remains on)	Refer to ABS Warning Light Remains ON [02/2019 - 12/2021]
   ABS warning light circuit (Does not come on)	Refer to ABS Warning Light does not Come ON [02/2019 - 12/2021]
   Brake warning light / red (malfunction) circuit (Remains on)	Refer to Brake Warning Light Remains ON [02/2019 - 12/2021]
   Brake warning light / red (malfunction) circuit (Does not come on)	Refer to Brake Warning Light does not Come ON [02/2019 - 12/2021]
   Brake warning light / yellow (minor malfunction) circuit (Remains on)	Refer to Brake Control Warning Light Remains ON [02/2019 - 12/2021]
   Brake warning light / yellow (minor malfunction) circuit (Does not come on)	Refer to Brake Control Warning Light does not Come ON [02/2019 - 12/2021]
   Slip indicator light circuit (Remains on)	Refer to Slip Indicator Light Remains ON [02/2019 - 12/2021]
   Slip indicator light circuit (Does not come on)	Refer to Slip Indicator Light does not Come ON [02/2019 - 12/2021]
   Brake hold standby indicator light circuit	Refer to Brake Hold Standby Indicator Light Circuit [02/2019 - 12/2021]
   Brake hold operated indicator light circuit	Refer to Brake Hold Operated Indicator Light Circuit [02/2019 - 12/2021]