C0245 Code: Wheel Speed Sensor Frequency Error

What the C0245 code means

The ABS module (EBCM) controls the anti-lock brakes and, on most modern vehicles, traction control and stability control too. When it detects a fault, it disables those functions and turns on the ABS and stability warning lights. The normal brakes keep working.

The module continuously compares the speeds of the four wheels. If one shows impossible frequency jumps or drifts away from the others without any wheel slip, it stores the C0245 code. Unlike the circuit codes, here the sensor does give a signal, but it is erratic.

The typical causes are a toothed ring (reluctor) with broken or rusty teeth, or with metal debris stuck to the sensor, a wheel bearing with play that changes the distance between the sensor and the ring, or tires of different sizes.

Important: many C and B codes are not generic. The definition on this page is the most widespread one, used by General Motors and most generic scan tools, but on other makes the same number can mean something else. Always confirm the code text with a scan tool that reads the right module (ABS, body or airbag).

C0245 code symptoms

• ABS and stability control warning lights on.
• The ABS kicks in at low speed for no reason, with pulsing in the pedal.
• The speedometer may fail on some vehicles.

Likely causes of the C0245 code

1. Toothed ring that is broken, rusty or dirty. The most common cause.
2. Sensor with metal debris on it, or poorly fastened. Confirm it by comparing its reading with the real value.
3. Wheel bearing with play. It changes the distance to the ring.
4. Tires of different sizes or heavily worn on one axle.
5. Wiring damaged near the wheel. Look for rubbing against the engine, the frame or the exhaust.

How to diagnose the C0245 code step by step

1. Compare the speeds of the four wheels on the scan tool while driving in a straight line.
2. Remove and clean the sensor and inspect its tip.
3. Inspect the toothed ring by turning the wheel slowly.
4. Check the bearing play.
5. Check the size and pressure of the tires.

How to fix the C0245 code

• Clean the sensor and the ring.
• Replace the ring, or the hub with bearing if it is damaged.
• Replace the sensor if the signal is still erratic.
• Match the tires.
• Clear the code and verify it with a road test.

Technical reference data

• All four wheels must read the same speed in a straight line, within a few km/h (a couple of mph).
• These values are approximate. Check the manufacturer data for your vehicle.

Brand-specific notes

Rust on the tone rings is the usual culprit on trucks that see road salt. Inspect the rings before you spend money on sensors.

C0245 on Chevrolet and GMC

This code is very common on Chevrolet Silverado and GMC Sierra pickups, and on Chevrolet Tahoe and Suburban, because of rust on the rings.

Frequently asked questions about C0245