Toyota CH-R Service Manual: TRAC does not Operate

Toyota CH-R Service Manual / Brake Control / Dynamic Control Systems / Vehicle Stability Control System / TRAC does not Operate

DESCRIPTION

When ABS, TRAC or VSC is operating, the skid control ECU (brake actuator assembly) blinks the slip indicator light to inform the driver that slippage occurred.

When in VSC off mode, or TRAC and VSC are disabled, the multi-information display in the combination meter assembly displays TRAC OFF message and the VSC OFF indicator light illuminates to inform the driver.

When a communication malfunction with the ECM is detected, TRAC and VSC are disabled. Also when the system is malfunctioning, TRAC and VSC are disabled and the indicator lights of related systems illuminate.

CAUTION / NOTICE / HINT

NOTICE:

When replacing the skid control ECU (brake actuator assembly), perform system variant learning.

Click here

PROCEDURE

1.	BRAKE PROBLEM CHECK

(a) Check if the slip indicator light was illuminated when TRAC did not operate.

OK:

The slip indicator light was illuminated.

HINT:

When a DTC is stored, the slip indicator light is illuminated and TRAC does not operate due to the fail-safe function.

(b) Check the operation condition of the VSC OFF switch (electric parking brake switch assembly) when TRAC did not operate.

OK:

The VSC OFF switch (electric parking brake switch assembly) had been operated to turn off TRAC when TRAC did not operate.

HINT:

When the multi-information display in the combination meter assembly displays TRAC OFF message, TRAC does not operate.

END

CHECK DTC

(a) Clear the DTCs.

Click here

Chassis > ABS/VSC/TRAC/EPB > Clear DTCs

(b) Turn the ignition switch off.

(d) Check the DTCs (vehicle stability control system) that are output.

Click here

Chassis > ABS/VSC/TRAC/EPB > Trouble Codes

Result	Proceed to
DTCs are not output.	A
Vehicle stability control system DTCs are output.	B

REPAIR CIRCUITS INDICATED BY OUTPUT DTCS

3.	CHECK VEHICLE

(a) Operate the VSC OFF switch (electric parking brake switch assembly) and check that the multi-information display in the combination meter assembly displays "Traction Control Turned Off" and the VSC OFF indicator light illuminates in accordance with the operation of the switch.

OK:

The multi-information display in the combination meter assembly displays "Traction Control Turned Off" and the VSC OFF indicator light illuminates in accordance with the operation of the switch.

INSPECT VSC OFF SWITCH CIRCUIT

4.	PERFORM TEST MODE (SIGNAL CHECK) INSPECTION (SPEED SENSOR CIRCUIT)

(a) Using the Techstream, perform a Test Mode (Signal Check) inspection sensor check and check that speed sensor Test Mode (Signal Check) inspection items change from incomplete to complete.

Click here

Chassis > ABS/VSC/TRAC/EPB > Utility

Tester Display
Signal Check

OK:

Speed sensor Test Mode (Signal Check) inspection items change from incomplete to complete.

INSPECT AND REPAIR MALFUNCTIONING SPEED SENSOR CIRCUIT

5.	PERFORM OPERATION CHECK DRIVING

(a) Operate the VSC OFF switch (electric parking brake switch assembly) and check that the system is not in TRAC off mode or VSC off mode.

(b) Check that no DTCs are output and that each warning light is not illuminated.

(c) Start off the vehicle on a low friction surface and check that TRAC operates when attempting to make the drive wheels slip.

OK:

TRAC operates when slip occurs when starting off.

NOTICE:

Even when the system is normal, VSC may not operate when the vehicle speed is low or TRAC may not operate due to a malfunction. Make sure that only the drive wheels slip during the procedure.
When confirming that the slip indicator light blinks, do not slip the drive wheels longer than necessary. Whether TRAC operated or not can be checked by reading the Freeze Frame Data when the system operated.
Pay attention to your surroundings when performing the procedure and depress the accelerator pedal with caution.

USE SIMULATION METHOD TO CHECK

REPLACE BRAKE ACTUATOR ASSEMBLY

Excessive Brake Pedal Travel (No Fluid Leaks and No Air in System)

DESCRIPTION Depending on the malfunction, the skid control ECU (brake actuator assembly) prohibits operation of the vehicle stability control system to protect components and prevent incorrect op ...

ABS does not Operate

DESCRIPTION When the vehicle stability control system is operating, as the input piston and output piston are not directly connected, the kickback of the brake pedal is minimal during ABS operati ...

Other materials:

Toyota CH-R Service Manual > Smart Key System(for Start Function): Power Source Mode does not Change to ON (IG and ACC)
DESCRIPTION If any of the following operations are performed, the certification ECU (smart key ECU assembly) receives a signal, and changes the power source mode. With the electrical key transmitter sub-assembly in the cabin, the engine switch is pressed. When the transmitter batt ...

Toyota CH-R Owners Manual > BSM (Blind Spot Monitor): RCTA function
The RCTA functions when your vehicle is in reverse. It can detect other vehicles approaching from the right or left rear of the vehicle. It uses radar sensors to alert the driver of the other vehicle's existence through flashing the outside rear view mirror indicators and sounding a buzzer ...