Traction Control

WARNING: This page is about a different car, the 2018 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.

The ABS module continuously monitors and compares the rotational speed of the drive wheels in relation to the non-driven wheels. When the drive wheels begin to spin faster than the non-driven wheels, 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. At the same time, the ABS module calculates how much engine torque reduction is required to eliminate the wheel slip and sends this torque reduction message along with a traction event message to the BCM and PCM over the HS-CAN. The BCM relays the traction event message to the IPC over the MS-CAN. When the PCM receives the torque reduction message, it adjusts engine timing and decreases fuel injector pulses to reduce the engine torque to the requested level. When the IPC receives the traction event message it flashes the stability-traction control indicator (sliding car icon). Once the driven wheel speed returns to the desired speed, the ABS module returns the solenoid valves in the HCU to their normal position, deactivates the hydraulic pump motor and stops sending the traction event and torque reduction messages. The PCM returns engine timing and fuel injectors to normal operation and the IPC extinguishes the stability-traction control indicator (sliding car icon). After the vehicle speed exceeds 100 km/h (62.1 mph), traction control is accomplished only through the PCM torque control.

Traction control can be disabled through the menu in the message center, refer to the Owner's Literature for instructions on disabling traction control. This is independent of the ABS and ESC, which cannot be disabled by the driver. When the driver disables traction control, the IPC communicates traction control status to the BCM along the MS-CAN. The BCM sends the message to the ABS module along the HS-CAN. The ABS module takes no further action in regards to traction control until the driver activates the function or until the ignition is cycled from OFF to ON.

Traction control can also be disabled using the traction control switch, if equipped. Pressing the switch once disables the traction control function. The system remains in the selected state until the driver enables the system by pressing the traction control switch once or until the ignition is cycled from OFF to ON. This is independent of ABS, ESC and RSC, all of which cannot be disabled by the driver. The ABS module takes no further action in regards to traction control until the driver activates the system or until the ignition is cycled from OFF to ON.

Traction control is disabled if there is a wheel speed sensor or solenoid valve DTC present in the ABS module. Traction control is also disabled if there is a communication error between the ABS module and the BCM or PCM. When traction control is disabled, the ABS module sends a message to the BCM along the HS-CAN which gateways the message to the IPC over the MS-CAN to illuminate the stability-traction control OFF indicator (sliding car OFF icon).