Fault-Code Library · Ignition
P0351: Ignition coil A primary / secondary circuit
The ECU detects an electrical fault in the ignition coil A control circuit.
Common symptoms
- •Misfire
- •Rough idle
- •Flashing engine light
- •Poor acceleration
Likely causes
- •Failed ignition coil
- •Damaged coil connector
- •Harness or ECU driver fault
- •Water or oil contamination around the coil
First checks
- •Inspect coil connector and wiring
- •Check for cylinder-specific misfire counters
- •Swap-test the coil only after confirming the circuit fault
Important
A circuit code is not only a worn spark plug; inspect power, ground, and command before replacing parts.
A fault code identifies a detected condition, not a failed part. Confirm manufacturer-specific subcodes and live data.
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