Roll Stability Control (RSC®) System
The 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 RSC® system also uses input from the steering wheel rotation sensor, the stability control sensor cluster (yaw rate, roll rate, longitudinal and lateral acceleration) 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 vehicle motion relative to the driver's intended course. If the ABS module determines from all these inputs 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 will assist with vehicle stability by adjusting engine timing and decreasing fuel injector pulses. When the IC receives this message, it will flash the stability/traction control indicator "sliding-car icon". 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 stability/traction control indicator.
If the anti-lock control system is disabled due to DTCs being present in the ABS module, the RSC® system will also be disabled. When the RSC® system is disabled due to DTCs being present, both the ABS warning indicator and the stability/traction control indicator will be illuminated.