P0352: OBD-II code P0352 flags a fault in ignition coil B — either the primary drive circuit is bad or the secondary spark path has failed.
MediumPowertrainIgnition
Symptoms
- Check engine light is on; the engine misfires on the cylinder(s) served by coil B.
- Rough idle, hesitation on acceleration, and reduced power because one cylinder is not firing properly.
- Fuel economy drops and unburned fuel through the misfiring cylinder can damage the catalytic converter over time.
Common causes
- A failed ignition coil B with an open or shorted primary winding — very common on coil-on-plug setups.
- Damaged wiring or a corroded connector at the coil, common when oil migrates into the connector.
- A worn spark plug increasing secondary voltage demand and stressing the coil until it fails.
What to do?
Swap coil B with a known-good coil from another cylinder and rescan; if the misfire follows the coil, replace it. Inspect the connector for oil intrusion. Replace worn spark plugs at the same time to prevent recurrence.