C0634

Q: 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.

Brake Pressure Sensor A/B Correlation

High severity

Brake pressure sensors A and B disagree beyond plausible deviation.

Common causes

One sensor drifted
One of the most commonly reported causes for this code — check this first.
high
Typical part cost: $220-1650
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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 C0634 mean?

C0634 means "Brake Pressure Sensor A/B Correlation". It is a generic OBD-II code that points to a fault in the chassis.

What are the most common causes of C0634?

one sensor drifted — 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?

This code can put the vehicle into limp or reduced-power mode. Avoid extended driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.

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