The anti-lock braking system uses wheel speed sensors to detect if a tire is about to stop rotating under heavy braking. A hydraulic control unit then rapidly pulses the brake pressure to that specific wheel, allowing the tire to maintain rolling traction. This keeps the driver in steering control and prevents the vehicle from entering an uncontrolled skid.
Scan the module for codes, the ABS light came on right after they hit a massive pothole.
When bleeding brakes on a car with ABS, you often need a scan tool to cycle the hydraulic pump to get all the trapped air out of the module.
Related terms
Brake assembly
A complete, pre-assembled unit containing the components needed to replace a vehicle's braking mechanism.
Caliper
The hydraulic clamp in a disc brake system that squeezes the brake pads against the rotor.
ESC
Electronic stability control automatically applies individual brakes to prevent skidding.
TCS
Traction Control System is an active safety feature that detects and prevents driven wheels from losing grip.