EXCITER RING – VOLVO ( 21980508 )

The Exciter Ring is attached to a part of the vehicle that is rotating at the same speed as the road wheel, such as the wheel hub, brake disc, CV joint or the drive shaft & has evenly spaced teeth integrally cast on or into the surface & is a crucial part of the ABS system. ABS sensors are installed directly next to this & the rotational movement of the ring is measured by the sensor signaling to the ABS system changes to traction & preventing the wheels from locking up during heavy braking.