P056E code meaning
Cold Start Turbocharger/Supercharger Boost Control A Performance
Powertrain system Generic code P05xx codes Check engine light
What P056E means
CARB requires every element commanded by the cold-start strategy to respond measurably in the commanded direction, with its own codes separate from the general monitoring of the same part. During catalyst heating the boost control is positioned deliberately – diesels close the variable turbine for load and heat, gasoline engines open the wastegate so heat reaches the catalyst. P056E means boost control A (the first or only charger) did not follow its cold-start target. Its only documented user is Stellantis: the 2025 Ram 3500 cab chassis with 6.7 L Cummins lists it among codes that can light the warning lamp, fixed by a PCM software update; customers noticed hard cold starts and raised cold idle. Ford and GM do not use it.
P056E at a glance
- Check engine lightYes, usually on
- Emissions testCan fail
- Limp modeNot expected
- Repair difficultyMedium
- Typical labor0.5 to 4 hours
- Clears after repairAfter a drive cycle
Symptoms of P056E
- Check engine light on
- Hard cold start or rough warm-up
- Otherwise usually unremarkable
Common causes of P056E
- Most likelyVariable turbine or wastegate actuator stiff (coking, cold)
- PossibleModule software or calibration
- PossibleVacuum or boost hose leaking
- Less likelyPosition or boost sensor faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Turbocharger actuatorBoost pressure sensorEngine control module
What each part of P056E means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 5 | Area: vehicle speed, idle control and auxiliary inputs. |
| 6E | The exact fault in that area. |
What to do next
- Note P056E 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 P056E
What does P056E mean?
P056E means "Cold Start Turbocharger/Supercharger Boost Control A Performance". CARB requires every element commanded by the cold-start strategy to respond measurably in the commanded direction, with its own codes separate from the general monitoring of the same part. It is a generic code, so it means the same on every make.
Is it safe to drive with P056E?
Usually yes, for a short time, if the check engine light is steady and the car drives normally. If the light flashes or the car runs badly, stop and have it checked.
Will P056E fail an emissions test?
Yes, it can. P056E 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 P056E to fix?
Difficulty: medium. A typical repair takes 0.5 to 4 hours of work. This is a job for a workshop.
Will P056E 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.