P034B
Crankshaft Position Sensor - Crankshaft Direction Incorrect
The crankshaft is rotating in the wrong direction relative to the expected reference — typically only seen on stop-start systems where the engine briefly counter-rotates after shutdown.
The crankshaft is rotating in the wrong direction relative to the expected reference — typically only seen on stop-start systems where the engine briefly counter-rotates after shutdown.
Common causes
- high
Stop-start residual reverse rotation
One of the most commonly reported causes for this code — check this first.
Typical part cost: $220-1320
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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
See related trouble codes
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Frequently asked questions
What does P034B mean?
P034B means "Crankshaft Position Sensor - Crankshaft Direction Incorrect". It is a generic OBD-II code that points to a fault in the ignition system or misfire.
What are the most common causes of P034B?
stop-start residual reverse rotation — 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 points to a problem that can cause damage or affect safety. Avoid driving and have the vehicle diagnosed promptly. Use the Wrenchify app for a full diagnosis specific to your vehicle.
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