Vehicle Stability Control System (For Hatchback With Separate Type Yaw Rate Sensor) Precaution

When there are malfunctions with terminal contact points or part installation problems, removal and installation of the suspected problem parts may return the system to the normal condition either completely or temporarily.

In order to determine the malfunctioning area, check the conditions at the time the malfunction occurred, such as DTC output and the Freeze Frame Data, and record them before disconnecting each connector or removing and installing parts.

Since the system may be influenced by malfunctions in systems other than the VSC system, be sure to check for DTCs in other systems.

Do not remove or install VSC parts such as the steering angle sensor or yaw rate sensor (deceleration sensor included) except when required, as they cannot be adjusted correctly after removal or installation.

Be sure to perform preparation before work and confirmation after work is completed by following the directions in the repair manual, when working on the VSC system.

Be sure to remove and install the ECU, brake actuator and each sensor, etc. with the ignition switch off unless otherwise specified in the inspection procedure.

If the ECU, brake actuator or a sensor has been removed and installed, it is necessary to check the system for problems after the parts have been reassembled. Check for DTCs using the Techstream, and also check that system functions and signals received by the ECU are normal using Test Mode.

If replacing the skid control ECU (brake actuator assembly), always replace it with a new one (if the skid control ECU (brake actuator assembly) is not replaced with a new one, DTCs may be stored).

NOTICE:

Do not use a skid control ECU (brake actuator assembly) from another vehicle. (display model, etc.)

Some DTCs cannot be cleared only by repairing the malfunctioning parts. If the DTC is output after repair work, turn the ignition switch off to clear the DTC.

NOTICE:

If a part is still malfunctioning even after the DTC is cleared, the DTC will be stored again.

Disable TRAC and VSC controls when using a chassis dynamometer.

1. When testing with a 2-wheel drum tester such as a speedometer tester, a combination tester for the speedometer and brake, a chassis dynamometer, or when jacking up the front wheels and turning the wheels, perform the following procedure to enter the inspection mode and stop the TRAC and VSC systems.
   Enter inspection mode to disable TRAC and VSC control when using a chassis dynamometer.
   

2. When testing with a 2-wheel drum tester such as a speedometer tester, a combination tester for the speedometer and brake, or a chassis dynamometer, enter Test Mode using the Techstream, or switch to VSC OFF mode to turn TRAC and VSC operation off using the VSC OFF switch.
   

   NOTICE:

   Secure the vehicle with the lock chain for safety.

   HINT:

   1. The vehicle may move unexpectedly out of the dynamometer because of TRAC and VSC operations.
      
   2. Pressing the VSC OFF switch does not disable TRAC and VSC operations completely.
      

The CAN communication system is used for data communication among the skid control ECU, the steering angle sensor (spiral cable sub-assembly), the yaw rate and deceleration sensor (yaw rate sensor) and other ECUs. If there is trouble in the CAN communication line, corresponding communication line DTCs are output.

If any CAN communication line DTC is output, repair the malfunction in the communication line and troubleshoot the VSC system after data communication becomes normal.

In order to enable CAN communication, a specific type of wiring is used for the CAN communication lines. The wiring used for each communication line is a twisted pair of wires of equal length. A bypass wire should not be used because the data being transmitted will be corrupted.