P20CC code meaning
Exhaust Aftertreatment Fuel Injector A Control Performance
Powertrain system Generic code P20xx codes Check engine light
What P20CC means
Unlike the circuit codes, this one judges what the hydrocarbon doser actually does. On the 6.6 L Duramax LML/LGH, GM table 15OBDG09 sets it when the outlet of the oxidation catalyst runs more than 300 °C hotter than its inlet for 180 s although no regeneration is under way and more than 900 s have passed since the last one; that heat can only come from fuel the doser should not be delivering. It is a Type A fault, so the MIL comes on after one trip. To keep the nozzle free, the same GM software pulses it briefly at 100 Hz at set soot levels. CARB requires makers to flag any injection fault that stops the filter from regenerating. Stuck positions have separate codes (P20CF, P20D0).
P20CC at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modePossible
- Repair difficultyHard
- Typical labor1 to 3 hours
- Clears after repairAfter a drive cycle
Symptoms of P20CC
- Check engine light on
- Unexpectedly high exhaust temperatures, possibly white smoke or fuel smell
- Higher fuel consumption
Common causes of P20CC
- Most likelyDoser leaking or dribbling fuel into the exhaust while closed
- PossibleCoked nozzle tip with distorted spray
- Less likelyExhaust temperature sensor before or after the catalyst reading wrong
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 P20CC 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. |
| CC | The exact fault in that area. |
What to do next
- Note P20CC 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 P20CC
What does P20CC mean?
P20CC means "Exhaust Aftertreatment Fuel Injector A Control Performance". Unlike the circuit codes, this one judges what the hydrocarbon doser actually does. It is a generic code, so it means the same on every make.
Is it safe to drive with P20CC?
Drive gently and only to a workshop. With P20CC the car can go into limp mode (reduced power) to protect itself.
Will P20CC fail an emissions test?
Yes, it can. P20CC 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 P20CC to fix?
Difficulty: hard. A typical repair takes 1 to 3 hours of work. This is a job for a workshop.
Will P20CC 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.