P0352
Ignition Coil B Primary Control Circuit/Open
Ignition / misfire
Generic OBD-II
High
What it means
P0352 means the engine control module detected an open or fault in the primary control circuit for ignition coil B. That coil fires the spark plug on its cylinder; when its circuit is open the cylinder misfires, so the engine runs rough, loses power, and can stall. Sustained misfiring also risks overheating the catalytic converter, so it's worth fixing quickly.
High
Can I keep driving? Not for long — a dead coil means a cylinder isn't firing, so the engine runs rough and can damage the catalytic converter. Drive as little as possible.
Common symptoms
What you'll notice
- Check-engine light on (may flash during an active misfire)
- Noticeable misfire, shaking, or rough idle
- Reduced power and hesitation on acceleration
- Possible stalling and increased fuel consumption
Common causes
Most likely first
- Failed ignition coil B (the most common cause)Likely
- Open, damaged, or corroded wiring/connector at the coilCommon
- Open in the coil's primary control (driver) circuit to the ECM/ignition moduleCommon
- Faulty coil-driver output in the ECM (less common)Less often
How to diagnose & fix
Work through it in order
- Read freeze-frame data and identify which cylinder coil 'B' serves on your engine.
- Inspect the coil's connector and wiring for damage, corrosion, or an open.
- Swap coil B with a known-good coil from another cylinder to confirm the coil itself.
- Check the primary control circuit for continuity back to the ECM.
- Replace the failed coil (and spark plug if worn), then clear and re-test.
FAQ
Quick answers
Is it safe to drive with P0352?+
No, not for long. A misfiring cylinder dumps raw fuel into the exhaust and can overheat and ruin the catalytic converter, especially if the light is flashing.
Can I just clear P0352?+
It returns within a drive cycle because the coil circuit is still open — the coil or its wiring has to be repaired.
Related codes
Often seen with P0352
Read & clear P0352 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX