Standard Motor Products ABS Wheel Speed Sensor

The sensors underneath the driver-assistance systems rather than in front of them: wheel speed, steering angle, parking ultrasonics, occupant classification. They are cheaper and more replaceable than the cameras and radar, and they fail more often, because they live where the road throws salt and stones.

Supplied by Standard Motor Products.

In the box: The sensor; Connector or pigtail where supplied.

Calibration required. This part must be calibrated to the vehicle after fitting. Without it the system does not fail safely — it reports confident, wrong readings.