Normal Operation and Fault Conditions

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

The PSCM calculates steering wheel rotation speed, angle and direction of rotation and sends the information to the ABS module over the HS-CAN2. A failure of the HS-CAN2, the PSCM or the internal sensors causes the ABS module to set one or more DTCs is set and the ABS warning indicator is illuminated.

PPT LA ABS MODULE FAULT TRIGGER CONDITIONS TABLE

DTC	Description	Fault Trigger Conditions
C0051:23	Steering Wheel Position Sensor: Signal Stuck Low	This DTC sets if the steering wheel position signal from the PSCM is unchanged for a predetermined amount of time.
C0051:27	Steering Wheel Position Sensor: Signal Rate of Change Above Threshold	This DTC sets if steering angle signal message sent from the PSCM indicates a higher rate of change than other ABS module inputs.
C0051:54	Steering Wheel Position Sensor: Missing Calibration	This DTC sets if the steering angle center position is not found and the speed or time limit is exceeded. This DTC automatically clears as soon as the center position is found.
C0051:62	Steering Wheel Position Sensor: Signal Compare Failure	This DTC sets when the ABS module detects a time-out failure, a quality factor failure, a plausibility failure of the yaw or active yaw signals or a plausibility failure of the wheel speed data. When this occurs, the steering angle center cannot be determined to be valid and the system triggers the steering angle center learning process.
C0051:64	Steering Wheel Position Sensor: Signal Plausibility Failure	This DTC sets when the ABS module determines the PSCM steering angle message is implausible when compared to the steering angle module value (based on the yaw rate sensor information). This DTC also sets if the long term offset compensation monitoring is completed after more than 30 km (18 miles) of straight driving resulting in a long term filtered steering angle offset greater than 15 degrees.
C0051:86	Steering Wheel Position Sensor:	This DTC sets in the ABS module when there is a time-out failure, quality factor failure or plausibility failure of the steering angle sensor data. When this occurs, the steering angle sensor center cannot be determined to be valid and the system triggers the relearn center process.