Antilock Brakes / Traction Control Systems: Service Precautions
Precautions1. Cautions for troubleshooting
(1) For malfunctions caused by a poor connection of terminals or parts, try reconnecting the relevant connector or parts. In some cases, this may temporarily or completely solve the problem.
(2) To locate the malfunctioning part, check the operational status, including the diagnostic code output and freeze frame data output at the time the malfunction occurred and record them before disconnecting each connector or removing/attaching the relevant parts Also, if a circuit open error code for instantaneous interruption monitoring is output, monitor instantaneous interruption before disconnecting connectors.
(3) Considering a possibility that system other than the brake control system is affecting the malfunction, check diagnostic codes for other systems.
2. Precautions for handling and procedures
(1) Unless otherwise specified for the check procedures, make sure that IG is OFF before removing or attaching actuators and sensors.
(2) When the actuators and sensors have been removed or installed, perform a test mode check and diagnostic code output check to make sure that the normal display is output after all parts have been installed.
(3) VSC-related parts adjustment may become faulty after removal or installation. Don't remove or install them unless necessary.
(4) When performing work related to VSC, follow the instructions in this manual and make sure to perform all preparation work and confirm completion of the work.
3. Fail safe function
(1) If an error occurred in a part of ABS/TRC/VSC brake assist system, relevant warning light and indicator light illuminate. At the same time, ABS, TRC, VSC, and brake assist system stop the operations.
NOTE:
EBD control continues as long as possible even when ABS control stops. If EBD control stops, the brake warning light illuminates.
4. Precautions for diagnostic codes
(1) As for some of the diagnostic codes, the warnings cannot be cleared only by repairing faulty parts.
(2) To clear the warning, diagnostic codes must be cleared or the procedures below must be followed.
Warning clearance procedures
CAUTION:
^ Be careful to drive and stop the vehicle while the warning is being issued because the system does not have a fail-safe function.
^ Currently issued diagnostic codes are stored in memory again.
5. Precautions for CAN communication
(1) Data communication in skid control computer (brake actuator ASSY) uses CAN communication. If CAN communication line has a problem, a diagnostic code of communication line error is output.
(2) If a CAN communication error code is output, repair the cause of fault in the communication line and troubleshoot the VSC system under normal data communication conditions.
(3) The length and route of each CAN communication line is specified. Therefore they cannot be fixed or repaired using bypass wire harness for a temporal fix or repair.