Fault-Code Library · ABS / stability control
C0040: Right front wheel-speed sensor circuit
The ABS module sees an implausible or missing signal from the right front wheel-speed sensor circuit.
Common symptoms
- •ABS warning
- •Stability-control warning
- •Cruise control disabled
- •Intermittent traction-control activity
Likely causes
- •Failed wheel-speed sensor
- •Damaged bearing encoder
- •Connector corrosion
- •Harness damage near the hub
First checks
- •Compare live wheel-speed values
- •Inspect sensor wiring and connector
- •Check bearing encoder or tone ring condition
Important
Front wheel-speed faults can affect ABS, stability control, and driver-assistance functions.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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