Turbocharger Wastegate Solenoid B Range/Performance
The turbocharger's wastegate solenoid B isn't responding correctly to the engine computer's commands, like a stuck valve that won't open or close properly. This prevents boost pressure from being controlled efficiently, affecting engine performance.
The ECM commands the wastegate solenoid B to modulate boost pressure by opening/closing a vent valve. It monitors the solenoid's electrical response (voltage/current) and verifies actual boost pressure matches commanded pressure within a specific range. If the solenoid doesn't respond or boost pressure deviates beyond threshold, a fault is detected.
| Parameter | Normal Range | Fault Condition |
|---|---|---|
| Solenoid Response Time | 50-200 milliseconds | >200ms or no response |
| Boost Pressure Differential | ±2 PSI of commanded | >5 PSI deviation |
Code P0249 is a moderate fault. You can generally drive to a workshop, but avoid long trips or high-load driving (motorway, uphill towing) until it is diagnosed. If the code keeps returning after clearing, or if you notice the symptoms listed above worsening, do not delay professional diagnosis. Many moderate codes have multiple possible root causes — a mechanic with live OBD data can identify the exact fault more efficiently than part-by-part trial and error.
Once the fault is repaired, P0249 can be cleared using any OBD-II scanner. Connect the scanner, navigate to "Clear Codes" or "Erase DTCs," and confirm. The check engine light turns off immediately.
The code will return if the root cause was not actually fixed. The ECM re-detects the fault within 1–3 drive cycles and sets the code again.