C0044
Right Front Wheel Speed Sensor Signal Erratic
Erratic pulses on the right front wheel speed sensor at speed. Wheel-speed signals feed ABS, ESC, traction control, transmission and odometer — a single dropped signal disables all of these safety functions until repaired.
- Check engine light: Not always
- Emissions related: No
- Repair difficulty: medium
Symptoms
- ABS warning light on
- ESC/stability control deactivated
- Possible reduced brake assist
- Speedometer may behave erratically
Common causes
Ordered by how often each turns out to be the cause.
- Encoder ring contaminated with metal debrisCommon
- Tone ring crackedPossible
- Connector with intermittent contact under vibrationLess likely
Parts involved
- Wheel Speed Sensor Fr
- Tone Ring
- Hub Bearing
C0044 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.