P236C code meaning
Cylinder 12 Pressure Too High
Powertrain system Generic code P23xx codes Check engine light
What P236C means
P236C flags combustion pressure in cylinder 12 above its allowed value. A public twelve-cylinder application does not exist. That a code of this kind need not involve a pressure sensor at all is shown by its cylinder-1 to -4 relatives P039B, P03A5, P03AF and P03B9 on Audi's 2015 S3 with the CYFB gasoline engine: faulty ECM software logged misfires in its primary detection window, switched on the EPC lamp and shut a cylinder off (P130A00); new ECM software solved it. On a diesel with real pressure sensing, a dripping injector, too much pilot fuel or a sensor drifting upward are the usual suspects. High peaks strain pistons, rings and gasket, so cutting the cylinder with reduced power is a plausible protective reaction.
P236C at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 5 hours
- Clears after repairAfter a drive cycle
Symptoms of P236C
- EPC or check engine lamp on
- Loss of power when the cylinder is switched off
- Harder combustion noise
Common causes of P236C
- PossibleEngine control software error (update available)
- PossibleInjector dripping or delivering too much pilot fuel
- Less likelyPressure sensor drifting upward
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Cylinder pressure sensor glow plugSensor wiringEngine control moduleFuel injector
What each part of P236C means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 3 | Area: ignition system or misfire. |
| 6C | The exact fault in that area. |
What to do next
- Note P236C 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 P236C
What does P236C mean?
P236C means "Cylinder 12 Pressure Too High". P236C flags combustion pressure in cylinder 12 above its allowed value. It is a generic code, so it means the same on every make.
Is it safe to drive with P236C?
Drive gently and only to a workshop. With P236C the car can go into limp mode (reduced power) to protect itself.
Will P236C fail an emissions test?
Yes, it can. P236C 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 P236C to fix?
Difficulty: medium. A typical repair takes 0.5 to 5 hours of work. This is a job for a workshop.
Will P236C 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.