OBD CodesWhat it means
Each ignition coil turns battery voltage into the high voltage needed for a spark. These codes are about the control circuit of a coil: an open circuit, a short, or a coil that does not respond. Coil A normally serves cylinder 1, coil B cylinder 2, and so on.
Codes in this group
| Code | Meaning |
|---|---|
| P0350 | Ignition coil circuit fault (coil not identified) |
| P0351 | Ignition coil A circuit fault (usually cylinder 1) |
| P0352 | Ignition coil B circuit fault (usually cylinder 2) |
| P0353 | Ignition coil C circuit fault (usually cylinder 3) |
| P0354 | Ignition coil D circuit fault (usually cylinder 4) |
| P0355 | Ignition coil E circuit fault (usually cylinder 5) |
| P0356 | Ignition coil F circuit fault (usually cylinder 6) |
| P0357 | Ignition coil G circuit fault (usually cylinder 7) |
| P0358 | Ignition coil H circuit fault (usually cylinder 8) |
| P0359 | Ignition coil I circuit fault (usually cylinder 9) |
| P0360 | Ignition coil J circuit fault (usually cylinder 10) |
| P0361 | Ignition coil K circuit fault (usually cylinder 11) |
| P0362 | Ignition coil L circuit fault (usually cylinder 12) |
Bank 1 is the side of the engine that has cylinder 1. Sensor 1 is before the catalytic converter and sensor 2 is after it. More terms explained.
What you may notice
- Misfire and shaking
- Loss of power
- Hard starting
- Flashing check engine light under load
Common causes
Most likely first:
- A failed ignition coil
- A loose or corroded coil connector
- Damaged wiring between computer and coil
- Worn spark plugs that overloaded the coil
What to check first
- Check the plug on the named coil is clipped in
- Replace overdue spark plugs: old plugs kill coils
- Avoid driving with a dead cylinder, to protect the catalytic converter
Have a mechanic confirm. A fault code tells you which system reported a problem, not which part has failed. The same code can have several causes, and they differ between car models. Use this page to understand the code, then have a qualified mechanic test the car before any part is replaced.
After the repair
Once the cause is fixed, the code can be cleared with a scan tool, or the warning light goes out by itself after several trips without the fault. Clearing a code without fixing the cause only hides it for a while. More about clearing codes.
Related codes
Crankshaft and camshaft timing do not agree (P0016), Engine misfire (P0300), Knock sensor (P0325), Crankshaft position sensor (P0335), Camshaft position sensor (P0340), Glow plugs (diesel) (P0380). All codes.
Written in November 2026. These are generic OBD-II codes, the same on all makes. Causes and repair steps differ between models.