P2335 — Ignition coil secondary circuit malfunction detected

The engine control unit detected a problem in the ignition coil's secondary circuit, which is responsible for generating the high voltage needed to create a spark in the spark plug. This can cause misfires, rough running, or poor engine performance.

Common causes

The cause is almost always one of a few things. Here they are — P2335 rarely comes from anything outside this list:

• Faulty ignition coil
• Damaged or corroded wiring/connectors
• Poor electrical connection or grounding
• Ignition control module malfunction
• Spark plug issues affecting coil load

Where to start

In the order a sensible mechanic would work — the cheap checks first, the expensive replacements only after:

1. Inspect and clean ignition coil connectors and wiring
2. Check and repair any damaged wiring or poor grounds
3. Test ignition coil output and replace if faulty
4. Inspect related spark plugs and replace if worn
5. Replace ignition control module if other fixes fail

That is what holds for P2335 in general. From here it depends on your engine — tell me which car it is and what it does, and I will give you the steps for it: real procedures, torque figures and diagrams instead of general advice.