C0066

Right Rear Wheel Speed Sensor Circuit Intermittent

Moderate severity

Intermittent open or short on the right rear wheel speed sensor circuit. Wheel-speed signals feed ABS, ESC, traction control, transmission and odometer — a single dropped signal disables all of these safety functions until repaired.

Common causes

Connector unseated
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $70-330
Wire chafe
A plausible cause — test and verify before replacing parts.
medium
Typical part cost: $70-330
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First things to check

1Confirm the code with a scan tool and check for additional related codes.
2Inspect the relevant sensors, wiring, and connectors for damage or corrosion.

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Related codes

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Frequently asked questions

What does C0066 mean?

C0066 means "Right Rear Wheel Speed Sensor Circuit Intermittent". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0066?

connector unseated; wire chafe; connector with intermittent contact under vibration — these are the most commonly reported causes. Verify with a proper diagnosis before replacing parts, or use the Wrenchify app for a vehicle-specific diagnosis.

Can I keep driving with this code?

The vehicle is usually drivable for short distances, but the problem can worsen or affect emissions. Diagnose and repair as soon as practical. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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