What it means
A general open-circuit fault has been detected on an ignition coil's primary or secondary winding (no specific cylinder identified). This code is set when the PCM cannot localise the fault to a single coil.
At a glance
- Usually lights the check-engine light
- Affects emissions; the car can fail an emissions test
How it works
The ignition coil primary circuit carries the module’s control current, while the secondary circuit produces the high voltage used to fire the spark plugs. P0350 sets when the engine control module detects a general electrical fault in a coil primary or secondary circuit but cannot identify one specific coil.
Common causes
Most likely first.
- Coil winding open
- Pin pushed back out of connector body
- Cracked solder joint inside the module or sensor
Symptoms
- Check-engine light
- Rough running or misfire
- Hard starting
- Reduced engine power
How to diagnose it
- Review freeze-frame data and misfire information to see when the general coil circuit fault occurs and whether a cylinder is identified separately.
- Inspect accessible ignition coil connectors and wiring for loose or pushed-back pins, broken insulation, or other damage.
- Check coil circuit fuses, power, grounds, and control wiring against the manufacturer’s wiring information.
- Test the primary and secondary circuits using the manufacturer’s specified checks to locate an open or short.
- If the wiring checks out, test the ignition coils and module or driver to identify the faulty component.
Common fixes
- Reconnect a loose coil connector or repair damaged or pushed-back terminals.
- Repair an open or short in the coil power, ground, or control wiring.
- Replace a coil that fails the manufacturer’s primary or secondary circuit checks.
- Repair or replace a failed ignition driver or module if testing confirms the fault.
Can I keep driving?
Avoid long trips and heavy acceleration if the engine is misfiring or hard to start; unburned fuel can damage the catalytic converter. If it runs very roughly or stalls, stop driving and arrange prompt diagnosis.
A code shows where the control module detected a fault, not always which part failed. Check the causes in order and confirm with a test before replacing parts. Have several codes? Check them together
This is a generic code: it means the same on every make. The car’s maker may add more detail in its own service information.