P0249 code meaning
Turbocharger/Supercharger Wastegate Actuator B Low
Powertrain system Generic code P02xx codes Check engine light
What P0249 means
The wastegate lets exhaust bypass the turbine to limit boost; actuator B is either a pulse-width-modulated solenoid on a pneumatic wastegate can or an electric actuator with a position sensor. B is the second turbo or actuator, so B codes only exist on engines with two. P0249 means the control circuit of actuator B reads low, typically the control wire shorted to ground. On GM's LGW twin-turbo less than 0.5 Ω to ground with the driver off in 10 of 20 samples sets it with the warning light in the first trip; older GM modules need two trips. Ford reports it on pneumatic wastegates after 2–3 s. Boost control is then switched off and only the spring-set base boost remains – less power, but no risk of overboost.
P0249 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 P0249
- Check engine light on
- Clearly less power, boost only at base level
- Uneven boost between the turbos
- Reduced engine power message possible
Common causes of P0249
- Most likelyControl wire of wastegate B chafed through to ground
- PossibleValve or actuator winding B shorted
- PossibleConnector damage or moisture
- Less likelyDriver stage in the engine module faulty
Check the most likely causes first. Replacing parts by guesswork is the most expensive way to clear a code.
Parts involved
Wastegate actuator bWastegate solenoid valveActuator wiring
What each part of P0249 means
| P | Powertrain system: engine, fuel system, ignition, emissions and transmission. |
| 0 | Generic code: it means the same on every make (SAE standard). |
| 2 | Area: fuel and air metering (injector circuit). |
| 49 | The exact fault in that area. |
What to do next
- Note P0249 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 P0249
What does P0249 mean?
P0249 means "Turbocharger/Supercharger Wastegate Actuator B Low". The wastegate lets exhaust bypass the turbine to limit boost; actuator B is either a pulse-width-modulated solenoid on a pneumatic wastegate can or an electric actuator with a position sensor. It is a generic code, so it means the same on every make.
Is it safe to drive with P0249?
Drive gently and only to a workshop. With P0249 the car can go into limp mode (reduced power) to protect itself.
Will P0249 fail an emissions test?
Yes, it can. P0249 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 P0249 to fix?
Difficulty: medium. A typical repair takes 0.5 to 2.5 hours of work. This is a job for a workshop.
Will P0249 clear itself after the repair?
Clear the code with a scanner after the repair. If the fault is fixed, it does not come back.