P0356 Code: Ignition Coil F Primary/Secondary Circuit Malfunction
🟠 Moderate severity · drivable
Drivable short-term, but cylinder 6 will misfire and raw fuel can damage the catalytic converter. Stop if the light flashes.
What P0356 means
There's an electrical fault in the ignition coil circuit for cylinder 6 (coil F). The computer can't command that coil to fire, so cylinder 6 loses spark and misfires — P0356 often appears alongside a P0306 cylinder 6 misfire for exactly this reason.
Symptoms
- Check engine light on (may flash)
- Misfire or rough idle on cylinder 6
- Loss of power
- Poor fuel economy
Common causes
- most common: Faulty ignition coil on cylinder 6 (coil F)
- common: Damaged wiring or a loose connector at the coil
- less common: Ignition driver failure inside the engine computer (PCM)
How to fix it
| Fix | DIY? | Typical cost |
|---|---|---|
| Swap the cylinder 6 coil with another cylinder to see if the misfire follows it | Yes | $0–20 |
| Replace the cylinder 6 ignition coil | Yes | $50–200 |
| Repair damaged coil wiring or connector | Mechanic | $50–150 |
Frequently asked questions
Which cylinder is coil F?
Coil F fires cylinder 6. P0356 is the cylinder 6 coil circuit.
How do I confirm a bad coil on P0356?
Swap the cylinder 6 coil with another cylinder and re-scan. If the misfire moves, the coil is bad.
Does P0356 cause a misfire?
Yes — without spark on cylinder 6, you get a misfire, so P0356 and P0306 often occur together.
Related codes
P0306
P0306 Code: Cylinder 6 Misfire Detected
P0350P0350 Code: Ignition Coil Primary/Secondary Circuit Malfunction
P0355P0355 Code: Ignition Coil E Primary/Secondary Circuit Malfunction
Related guide: The 10 Most Common Check Engine Codes →
Updated 2026-08. This page is informational and not a substitute for professional diagnosis.