Code result
C0040
Right Front Wheel Speed Sensor Circuit
Moderate severity
What it means
The ABS control module has detected a fault in the right front wheel speed sensor circuit. Loss of wheel speed information disables ABS and stability control, and a separate ABS warning lamp is illuminated.
Is it safe to drive?
Use caution
The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical.
Most likely causes
Wheel speed sensor failed
highOne of the most commonly reported causes for this code — check this first.
Tone ring damaged or contaminated
mediumA plausible cause — test and verify before replacing parts.
Wiring break or chafe at wheel arch
mediumA plausible cause — test and verify before replacing parts.
Wheel hub bearing with integrated sensor ring failed
lowLess common, but worth ruling out after the more likely causes.
Related help
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