Modern engines have one coil-on-plug ignition coil per cylinder, with the output stage either in the engine module or in the coil itself. P0355 monitors the primary control circuit of coil E – the line from the engine module to the coil or its built-in output stage – for an open circuit or high resistance. GM's module measures the voltage with its low-side driver off and flags an open circuit above 30 kΩ in 50 of 63 samples (2018 engines in the first trip, older ones after two); Ford checks continuously within 1 s, expecting a primary-current feedback for every ignition command, and shuts off injection to that cylinder for 30 s at a time. Short circuits and the secondary side have their own codes (P2300 ff). Coil E usually serves cylinder 5, but the assignment is up to the manufacturer.
Medium severity. Can I keep driving?Drive as little as possible. If you feel jerking or the light flashes, stop: a misfire can damage the catalytic converter.
Symptoms
- Check engine light on
- Misfire and rough running on cylinder 5, often also P0305
- Loss of power, jerking under load
- Cylinder shut off (injection off), risk to the catalyst if driven on
Most likely causes
- Ignition coil E faulty (output stage in the coil or primary winding open)
- Connector at the coil corroded, loose or with a spread pin
- Control, supply or ground wire open or chafed
- Fuse or relay of the coil supply (then usually several codes)
- Driver in the engine module faulty
What to check, in order
Start with the simplest. You can tick off each step.
Good to know
- Repair difficulty: easy
- It can trigger limp mode.
- It affects emissions.
What each character of P0355 means
- P: Powertrain: engine and transmission
- 0: Generic code: same on every make
- 3: Ignition and misfires
- 55: Specific fault in that system
Frequently asked questions
Can I keep driving with code P0355?
Drive as little as possible. If you feel jerking or the light flashes, stop: a misfire can damage the catalytic converter.
What causes code P0355?
The most common causes are: ignition coil E faulty (output stage in the coil or primary winding open); connector at the coil corroded, loose or with a spread pin; control, supply or ground wire open or chafed.
Related codes
- P2312Ignition Coil E Primary Control Circuit Low
- P2313Ignition Coil E Primary Control Circuit High
- P2314Ignition Coil E Secondary Circuit
- P0350Ignition Coil Primary/Secondary Circuit/Open
- P0305Cylinder 5 Misfire Detected
- P0300Random/Multiple Cylinder Misfire Detected
Sources
- gsi.ext.gm.com: 18OBDG03A Engine Diagnostics
- gsi.ext.gm.com: 16OBDG03 Engine Diagnostics
- newtonnet.co.uk: fordobd2012
- fordservicecontent.com: OBD Operations Summary Gasoline 2020 2023
Values and procedures vary by manufacturer. If it affects brakes, steering, fuel or high voltage, see a professional. Updated: 2026-11-04. How we build these pages.