Anti-Lock Brake System (ABS) and Stability Control - System Operation and Component Description

the ignition is cycled from ON to OFF and then back to ON again. If there are no other customer concerns, symptoms, indicators or Diagnostic Trouble Codes (DTCs), the stability-traction control indicator may have been illuminated due to these environmental or driving conditions.

Selectable Driving Modes

The MODE switch in the center of the instrument panel allows the driver to change between 4 driving modes. These driving modes alter the throttle response, shift patterns, EPAS feel and stability control intervention thresholds. Toggling the switch causes the FCIM to send messages to the PCM, PSCM, ABS module and IPC message center. The IPC message center displays the current selected mode. The PCM, PSCM and ABS module respond to the message by modifying their operation according to a preprogrammed set of instructions.

Normal : delivers a balanced combination of comfort, control and handling. Snow-Wet : provides increased handling, braking and control during poor weather conditions. Sport : provides increased steering, throttle and shift responses. Track : provides increased steering, throttle and shift responses as well as modifying the threshold for AdvanceTrac intervention.

One or more of the selectable drive modes is disabled if Diagnostic Trouble Codes (DTCs) are present in the PCM, PSCM or ABS module. If the selectable drive modes are disabled, the IPC message center displays Drive Mode Selection Not Available when the switch is toggled.

Launch Control

The launch control feature works in conjunction with the stability control system and PCM to maximize traction from a standing start acceleration in a straight line. Launch control enables a unique "drag start" traction control calibration designed for high grip surfaces. The system allows the driver to set and hold a desired launch RPM depending on tire temperature, surface condition or weather.

The driver activates and configures the launch control feature through the message center, see the Owner's Literature for specific information. The launch control system can only be activated when the stability control system is fully enabled. Once activated, the launch control feature remains ON until the driver deactivates it, the system does not reset when the ignition is cycled.

Line Lock

The line lock feature works in conjunction with the stability control system to "lock" the front brakes and allow the rear wheels to spin freely during throttle application to achieve maximum traction prior to use at a race track. The line lock feature is intended for use at race tracks only and should not be used on public roadways.

The driver initializes the line lock feature through the message center, see the Owner's Literature for specific information. Once initialized, the line lock feature is not activated and the vehicle brakes function normally. Line lock remains initialized up to 40 km/h (25 mph), once vehicle speed exceeds 40 km/h (25 mph) the line lock feature is automatically cancelled. Following initialization the line lock feature can be engaged, once engaged the ABS module closes isolation valves in the HCU to maintain the brake pressure in the front brake calipers while allowing the rear wheels to spin freely and a count-down timer begins. If the line lock feature is not used within this time limit or a vehicle condition requires the line lock feature to deactivate, the line lock feature is deactivated. Pressing the brake pedal while the line lock feature is activated automatically deactivates the line lock feature and normal brake function resumes.

Component Description

Anti-Lock Brake System (ABS) Module

The ABS module is attached directly to the HCU and is the electronic control unit for all of the ABS and stability control systems. The ABS module monitors all sensor inputs and all CAN messages relating to ABS and stability control, then directly controls the solenoid valves and the hydraulic pump motor in the HCU. The ABS module is available separately for service.

When a new ABS module is installed, it must be programmed with the vehicle configuration information and programmed with the latest level of module software. Refer to: Module Configuration - System Operation and Component Description (418-01 Module Configuration, Description and Operation).

When an ABS or stability control system fault has been corrected or a new component has been installed, the