What are the common causes of P25A1?

Turbo B vane actuator stuck. Boost control solenoid B failed. Boost position sensor B out of range. Carbon on the turbo B variable vanes. Leak in the boost reference line to turbo B.

Watch boost control B position live data. Sweep the turbo B actuator with a scan tool. Inspect the turbo B vane linkage for carbon binding. Test the boost control solenoid B. Check the boost reference line to turbo B for leaks. Clear the code and retest.

P25A1

Turbocharger B Boost Control Position At High Limit

System: Speed and idle control (P code)
Lamp: Check Engine Light
Category: Powertrain - Computer and Auxiliary Controls

What it means

P25A1 means Turbocharger B Boost Control Position At High Limit.

Check these first

Turbo B vane actuator stuck
Boost control solenoid B failed
Boost position sensor B out of range
Carbon on the turbo B variable vanes
Leak in the boost reference line to turbo B

What to do next

Watch boost control B position live data
Sweep the turbo B actuator with a scan tool
Inspect the turbo B vane linkage for carbon binding
Test the boost control solenoid B
Check the boost reference line to turbo B for leaks
Clear the code and retest

Look up another code

Code or symptom

Enter a full code or a symptom. Press / to search. How to read a code

Type a code above, or start from a symptom or a common code.

Updated

Generic SAE J2012 definition. Last updated 2026-10-10.