ABS rings are fitted to either the driveshaft or the wheel hub of a car and work together with sensors to provide wheel speed information to the ECU.
There are two types of ABS sensors: passive and active.
A passive sensor requires an ABS ring that inducts a magnetic field, thus producing a voltage that the ECM (engine control module) monitors. They look like a castellated metal ring.
An active sensor requires a magnetic ABS ring. This type is usually found in a hub bearing and looks like an oil seal.
ABS rings are found on all the four wheels of an ABS equipped vehicle.
Failure and replacement:
ABS rings are susceptible to corrosion and damage and they can often be missing from new CV joints. The rings are easily damaged when removed; therefore the best practice would be to fit a new ring.
A warning light will come up on the dashboard if the ring is faulty and will result in an MOT failure. A damaged ABS ring can only be identified by visual inspection.
• ADM57101 – Ford Maverick (2001-2004)
• V10-1494 – Audi (1995-2001)
ABS rings can be found on MAM Autocat+ and the F:Drive under Hydraulics>Brake Hydraulics. All parts are available through FPS on same/next-day delivery.