P0393
Camshaft Position Sensor B Circuit High
Cam sensor B on bank 2 above upper plausibility — open signal or short to B+. The camshaft position sensor identifies which cylinder is on the compression stroke — without it the ECM cannot run sequential injection or coil-on-plug ignition correctly.
Cam sensor B on bank 2 above upper plausibility — open signal or short to B+. The camshaft position sensor identifies which cylinder is on the compression stroke — without it the ECM cannot run sequential injection or coil-on-plug ignition correctly.
Common causes
- high
Open signal line
One of the most commonly reported causes for this code — check this first.
Typical part cost: $70-550
- low
Connector pins corroded - high contact resistance
Less common, but worth ruling out after the more likely causes.
Typical part cost: $70-550
See all causes + fix costs
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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 P0393 mean?
P0393 means "Camshaft Position Sensor B Circuit High (Bank 2)". 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 P0393?
open signal line; connector pins corroded - high contact resistance; supply wire pinched against b+ source — 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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