Stability Assist

The stability assist system recognizes critical driving conditions, and stabilizes the vehicle by individually braking each wheel and performing engine control intervention without the need to actuate the brake or accelerator pedal.

The stability assist provides a further function known as Electronic Stability Program (ESP) to the ABS, Traction Control System (TCS) and the Electronic Brake Distribution (EBD). Whereas the ABS/TCS function controls wheel slip during braking and acceleration (longitudinal dynamics), the active yaw control stabilizes the vehicle about its vertical axis.

Sensors measure steering wheel position, brake master cylinder pressure, yaw rate and lateral acceleration. This makes it possible to compare driver's intention with momentary vehicle behavior so that in the event of the vehicle becoming unstable, the stability assist system can initiate the appropriate corrective action.

The stability assist module is self-monitoring. When ignition switch is turned to RUN position, the module will perform a preliminary electrical check, and at about 12 MPH, the pump motor is turned on for about 1/2 second. Any malfunction of the stability assist system will cause the stability assist system to shut off, the ABS indicator to illuminate and the power assist braking system to function normally.

The stability assist system status is indicated by a stability assist warning light in the stability assist/traction control switch. The illuminated stability assist/traction control switch indicates stability assist system which is switched off. In vehicles with a message center the message ADVANCETRACOFF is displayed. If a failure is detected somewhere in the stability assist system which affects either the yaw control or traction control functions, the stability assist indicator will be illuminated. The anti-lock brake function will continue to work as designed, unless the Yellow ABS warning indicator is also illuminated. The normal brake function will always occur, unless the Red brake warning indicator is illuminated.

DTC C1963 (stability control inhibit warning) is stored if the stability assist warning indicator has been turned on because system could not confirm the straight-ahead position for more than 30 seconds with vehicle speed greater than 11 MPH. This DTC can also be stored if PRNDL or reverse switch has failed, chassis modifications have been made that were not authorized by manufacturer, a NEW stability assist module may have been installed and was not calibrated, or vehicle is driven with continuous swerving, sliding or tire spinning. There is no test procedure for this DTC.