An anti-lock braking system (ABS) is a safety anti-skid braking system used on vehicles.
ABS operates by preventing the wheels from locking up during braking, thereby maintaining tractive contact with the road surface
If your ABS light is on, you will need a diagnostic scanner that can read ABS Fault Codes.
Car owners quite often use generic scanners to read ABS codes which results in no-fault codes being retrieved.