WSS — ABS Wheel Speed

What it tells you

A passive wheel-speed sensor generates an AC sine wave that grows in amplitude and frequency as the wheel spins up. The scope shows what a scan tool averages away — a chipped tone-ring tooth, a low-amplitude signal from excessive air gap, or the one-wheel dropout behind an intermittent ABS code.

Healthy vs fault

Toggle Fault overlay on the scope above to drop the faulty capture over the healthy one. Seeing both traces on the same graticule is how you train your eye for the difference — the deviation that names the fault.

Symptoms this catches

• ▸abs light
• ▸traction control
• ▸speed sensor
• ▸tone ring
• ▸intermittent abs
• ▸dropout

Watch the walkthrough

Kits that capture this signal