P0356 code meaning
Ignition Coil F Primary Control Circuit/Open
Powertrain system Generic code P03xx codes Check engine light
What P0356 means
P0356 monitors the primary control circuit of ignition coil F – the line from the engine module to the coil or to its built-in output stage – for an open circuit or high resistance. Coil F usually serves cylinder 6, so the code only occurs on engines with at least 6 cylinders. GM's 6.2-litre V8s (LT4, LT5) flag an open circuit above 30 kΩ with the driver off in 50 of 63 samples, after two trips. Ford checks continuously from 200 rpm within 1 s, expecting a primary-current feedback for every ignition command, and then shuts off injection to that cylinder for 30 s at a time to protect the catalyst. GM bulletin PIP5038B describes coils on the 3.6-litre V6 (LLT) overheating from a permanently switched-on control signal; PIP5147 advises checking coil connectors for water. Short circuits have their own codes (P2315 ff).
P0356 at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyEasy, DIY possible
- Typical labor0.3 to 1.5 hours
- Clears after repairAfter a drive cycle
Symptoms of P0356
- Check engine light on
- Misfire and rough running on cylinder 6, often also P0306
- Loss of power, jerking under load
- Cylinder shut off (injection off), risk to the catalyst if driven on
Common causes of P0356
- Most likelyIgnition coil F faulty (output stage in the coil or primary winding open)
- Most likelyConnector at the coil corroded, wet or with a loose pin
- PossibleControl, supply or ground wire open or chafed
- Less likelyDriver in the engine module faulty or software (permanent dwell)
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Ignition coil fIgnition wiringEngine control module
What each part of P0356 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 3 | Area: ignition system or misfire. |
| 56 | The exact fault in that area. |
What to do next
- Note P0356 and any other codes stored with it: several codes together often point to one cause.
- Check for loose connectors and damaged wiring around the parts the code names.
- Check open recalls for your car: some faults are fixed for free by the dealer. Enter your VIN.
- Clear the code only after the repair. If it comes back, the fault is still there.
Buying a used car? Scan it for stored codes before you pay. A recently cleared memory can hide a problem.
Questions about P0356
What does P0356 mean?
P0356 means "Ignition Coil F Primary Control Circuit/Open". P0356 monitors the primary control circuit of ignition coil F – the line from the engine module to the coil or to its built-in output stage – for an open circuit or high resistance. It is a generic code, so it means the same on every make.
Is it safe to drive with P0356?
Drive gently and only to a workshop. With P0356 the car can go into limp mode (reduced power) to protect itself.
Will P0356 fail an emissions test?
Yes, it can. P0356 is emissions-related, so most inspection programs fail a car while it is stored or while the check engine light is on.
How hard is P0356 to fix?
Difficulty: easy. A typical repair takes 0.3 to 1.5 hours of work. A careful DIY repair is possible with basic tools and a scanner.
Will P0356 clear itself after the repair?
After the repair the car has to complete a drive cycle (a mix of city and highway driving) before the test runs again. Until then the readiness monitor shows "not ready", which can fail an inspection.