P2C31
Ignition Coil Primary Circuit Fuse B
The ECM detects an open or blown fuse on the ignition coil primary supply circuit B. Affected coils receive no operating voltage.
The ECM detects an open or blown fuse on the ignition coil primary supply circuit B. Affected coils receive no operating voltage.
Common causes
- high
Primary supply fuse blown by short circuit
One of the most commonly reported causes for this code — check this first.
Typical part cost: $20-330
- medium
Shorted ignition coil drawing excess current
A plausible cause — test and verify before replacing parts.
Typical part cost: $20-330
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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
See related trouble codes
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Frequently asked questions
What does P2C31 mean?
P2C31 means "Ignition Coil Primary Circuit Fuse B". It is a generic OBD-II code that points to a fault in the auxiliary emission controls.
What are the most common causes of P2C31?
primary supply fuse blown by short circuit; shorted ignition coil drawing excess current — 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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