P20CE code meaning
Exhaust Aftertreatment Fuel Injector A Control Circuit High
Powertrain system Generic code P20xx codes Check engine light
What P20CE means
The control line of the hydrocarbon doser is shorted to battery voltage. GM's diesel tables 18OBDG04 and 25OBDG04A detect it while the driver is switched on: current above roughly 8 to 11 A for a set time, or above about 16 to 22 A at once, counts as a short to power. GM rates it Type B, so the MIL follows after two trips; the LML/LGH Duramax (15OBDG09) uses a voltage check in the on state. The doser can then no longer be opened on command. Hino's J08E manual names P20CE among the codes to clear before diagnosing a regeneration complaint. Open circuit and short to ground are P20CB and P20CD.
P20CE at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyMedium
- Typical labor0.5 to 2.5 hours
- Clears after repairWhen cleared with a scanner
Symptoms of P20CE
- Check engine light on
- Active regeneration not possible
- Rising soot load, later reduced power
Common causes of P20CE
- Most likelyControl wire touching a powered wire in a damaged harness
- PossibleDoser solenoid with shorted turns drawing too much current
- Less likelyFaulty output stage in the engine control module
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Aftertreatment fuel injector
What each part of P20CE means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 2 | Generic code (second SAE range): it means the same on every make. |
| 0 | Area: fuel and air metering and auxiliary emission controls. |
| CE | The exact fault in that area. |
What to do next
- Note P20CE 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 P20CE
What does P20CE mean?
P20CE means "Exhaust Aftertreatment Fuel Injector A Control Circuit High". The control line of the hydrocarbon doser is shorted to battery voltage. It is a generic code, so it means the same on every make.
Is it safe to drive with P20CE?
Drive gently and only to a workshop. With P20CE the car can go into limp mode (reduced power) to protect itself.
Will P20CE fail an emissions test?
Yes, it can. P20CE 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 P20CE to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P20CE clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.