OBD-II Code C0031 — What It Means & How to Fix It

What Does This Error Mean?

C0031 means your vehicle's computer has detected a problem with the right front wheel speed sensor. Wheel speed sensors tell the ABS system how fast each wheel is spinning. When one fails, the ABS and traction control systems may stop working. Your brakes will still work normally, but the anti-lock function may be disabled. This is a common repair that most mechanics can handle.

Affected Models

All vehicles 1996+ with ABS
Common in GM cars and trucks
Common in Chevrolet Tahoe, Silverado, and Malibu
Common in GMC Sierra and Yukon
Also seen in some Pontiac and Buick models

Common Causes

Failed or damaged right front wheel speed sensor
Broken, corroded, or cut wiring in the sensor circuit running to the right front wheel
Damaged tone ring (the toothed ring the sensor reads) on the right front hub or axle
Loose or corroded electrical connector at the wheel speed sensor
ABS control module fault causing incorrect reading of the sensor signal

How to Fix It

Check the ABS and traction control warning lights on your dashboard. If both are on, this confirms the ABS system is disabled. Your regular brakes still work, but you have lost anti-lock function.

In slippery conditions like rain or snow, your wheels can lock up when braking hard without ABS. Drive more cautiously.
Inspect the wiring harness running to the right front wheel. This wire flexes constantly as the wheel turns and suspension moves. It is prone to breaking or chafing. Look for cuts, bare wires, or corrosion at the connector.

Follow the wire from the sensor (at the wheel hub) up into the wheel well. Damage is often found where the wire bends most.
Visually inspect the wheel speed sensor itself. It is a small cylindrical sensor bolted to the hub or steering knuckle, positioned very close to the toothed tone ring. Look for physical damage, cracks, or heavy rust that could affect its reading.

Sensors are usually held on by one or two bolts and cost $20–$60 each for most vehicles.
Check the tone ring for damaged or missing teeth. The tone ring is the metal ring with evenly spaced teeth that the sensor reads. It is usually on the wheel bearing hub or CV axle. Damaged teeth cause irregular signals.

A damaged tone ring means the hub assembly or bearing will likely need to be replaced along with the sensor.
Replace the faulty sensor and clear the code. Most sensors require only basic tools to replace. After clearing the code, drive at least 15 mph to let the system re-read the wheel speeds and confirm the repair.

If the code returns after replacement, suspect the wiring or tone ring rather than a second faulty sensor.

When to Call a Professional

Wheel speed sensor replacement is a moderate DIY repair if you are comfortable working on brakes. If you are not, a technician can handle it. Expect to pay $150–$300 including parts and labor for a single sensor. If the tone ring is damaged, it may require hub or bearing replacement, which costs $300–$600.

Frequently Asked Questions

Is it safe to drive with C0031?

Yes, your regular brakes still work. But your ABS and traction control are likely disabled. This means your wheels can lock up during hard braking on slippery surfaces. Avoid driving in icy or wet conditions until you fix it. Get it repaired as soon as reasonably possible.

Can I replace a wheel speed sensor myself?

If you are comfortable with basic mechanical work, yes. Sensors are usually held by one bolt and plug in with a connector. You will need to safely raise the vehicle and remove the wheel for access. If you have never worked on brakes or suspension before, have a mechanic do it.

Why did my ABS light come on but not my regular brake light?

The regular red brake warning light is for your hydraulic brake system. The orange or yellow ABS light is for the anti-lock braking electronics. They are two separate systems. C0031 affects only the ABS electronics, not your actual brake pressure or brake pads. Your brakes will feel and work the same — you just lose the anti-lock feature.