AdvanceTrac® with Roll Stability Control (RSC®) System

The AdvanceTrac® with Roll Stability Control (RSC®) system is controlled by the ABS module and uses the same wheel speed sensors and tone rings that are used for the anti-lock control system. The AdvanceTrac® with RSC® system also uses input from the steering wheel rotation sensor on Hydraulic Power Assist Steering (HPAS) -equipped vehicles, the Power Steering Control Module (PSCM) on Electronic Power Assist Steering (EPAS) -equipped vehicles, inertial signals (such as yaw and roll rate and lateral and longitudinal acceleration) from the Restraints Control Module (RCM), and information from other modules sent over the HS-CAN bus to help maintain vehicle stability. The ABS module uses all of these inputs to continuously monitor the vehicle's direction of travel relative to the driver's intended course. If the ABS module determines from all these inputs that the vehicle is unable to travel in the intended direction or that conditions exist for a potential roll-over event, it modulates brake pressure to the appropriate brake caliper(s) by opening and closing the appropriate solenoid valves inside the HCU while the hydraulic pump motor is activated. At the same time, the ABS module sends a message over the HS-CAN bus that a stability event is taking place. When the PCM receives this message, it adjusts engine timing and decrease fuel injector pulses. When the IC receives this message, it flashes the sliding-car icon (twice per second). Once the stability condition has been corrected, the ABS module returns the solenoid valves in the HCU to their normal position, deactivates the hydraulic pump motor and sends another message over the HS-CAN bus indicating that the event has ended. The PCM returns engine timing and fuel injectors to normal operation and the IC extinguishes the sliding-car icon.

If the anti-lock control system is disabled due to DTCs being present in the ABS module, the AdvanceTrac® with RSC® system is also disabled. When the AdvanceTrac® with RSC® system is disabled due to DTCs being present, the sliding-car icon is illuminated. In some cases, the sliding-car icon illuminates in conjunction with the yellow ABS warning indicator.