P0355 — Ignition Coil E Primary/Secondary Circuit
High severityWhat it means
P0355 is stored when the engine control unit sees a fault involving coil E's primary/secondary circuit. Ignition coils step battery voltage up to the tens of thousands of volts needed to fire the spark plugs, so a circuit fault causes a misfire on the affected cylinder. The control unit has flagged this circuit or signal as outside its normal operating range.
Common symptoms
- Misfire, rough idle and shaking
- Hesitation and power loss
- Flashing or steady check engine light
Likely causes
- A wiring, connector or ground problem in the circuit
- A failed sensor or actuator in the circuit
- Failed coil E
- Coil driver, wiring or connector fault
What to check first
- Inspect the connector and wiring for damage, corrosion or loose pins
- Swap coil E with a neighbouring cylinder and see if the fault follows
- Inspect the coil connector and primary wiring
Can you keep driving?
A coil fault means an active misfire that can damage the catalytic converter; limit driving and stop if the light flashes.
Frequently asked questions
What is the most common cause of P0355?
The most likely cause is: A wiring, connector or ground problem in the circuit. Several other faults can set P0355 as well, so confirm the real cause with live data and the checks above before replacing any parts.
Can I just clear P0355 and keep driving?
Clearing P0355 with an OBD2 scanner turns the warning light off, but if the underlying fault has not been repaired the code will usually come back within a few drive cycles. Fix the cause first, then clear the code to confirm the repair worked.
How serious is P0355?
P0355 is a high-severity code. Diagnose and repair it as soon as possible, because continuing to drive can cause further damage or leave you stranded.
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