Curve Control

WARNING: This page is about a different car, the 2023 Lincoln Nautilus. However, it is still accessible from the selected car via links, so may be relevant.

The ABS module continuously monitors the vehicle motion relative to the intended course. This is done by using sensors to compare the steering wheel input, the yaw rate sensor input, the lateral acceleration sensor input and the longitudinal acceleration sensor input with the actual vehicle motion. On vehicles without adaptive steering, steering angle information is calculated by the PSCM and sent to the ABS module over the HS-CAN2. On vehicles with adaptive steering, steering angle information is sent by the SASM over the HS-CAN2. Vehicle yaw rate, lateral acceleration and longitudinal acceleration information is sent to the ABS module from the RCM over the HS-CAN2. If the ABS module determines from the inputs the vehicle is experiencing over-steer or under-steer while traveling through a curve, the module sends a curve control event message over the HS-CAN2 to the GWM. The GWM relays this message to the PCM over the HS-CAN1 and to the IPC over the HS-CAN3. When the PCM receives this message, it assists with curve control by adjusting engine timing and decreasing fuel injector pulses. When the IPC receives this message, it flashes the stability-traction control indicator (sliding car icon). The ABS module continues to monitor the sensor inputs while the PCM assists with curve control. If the ABS module determines PCM intervention is insufficient to control the stability event, the ABS module 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. Once the vehicle instability has been corrected, the ABS module returns the solenoid valves in the HCU to their normal position, deactivates the hydraulic pump motor and stops sending the curve control event message. The PCM returns engine timing and fuel injectors to normal operation and the IPC extinguishes the stability-traction control indicator (sliding car icon).

The curve control system does not operate with the transmission in REVERSE. The ABS module disables the curve control system if there are any wheel speed sensor, stability sensor or steering angle sensor Diagnostic Trouble Codes (DTCs) present in the ABS module. The curve control system is also disabled if there is a communication error between the ABS module and the PSCM, the ABS module and the RCM or the ABS module and the SASM (if equipped). When the curve control system is disabled, the ABS module sends a message over the HS-CAN2 to the GWM. The GWM relays this message over the HS-CAN3 to the IPC to illuminate both the stability-traction control indicator (sliding car icon) and the stability-traction control disabled indicator (sliding car OFF icon).