P00AFTurbocharger/Supercharger Boost Control A Module Performance
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- Boost control A here is an electronic actuator with its own electronics (a "smart" actuator), usually on the variable turbine geometry, with its own position sensor and controlled over a data bus or a pulsed signal. It checks itself and reports internal faults to the engine control module; documented examples are pattern errors, overcurrent and checksum errors. The control module cannot narrow down a fault inside the actuator further. P00AF is set when actuator A reports such an internal fault. Manufacturer bulletins recommend checking the vane mechanism for free movement and, if it moves freely, replacing only the actuator rather than the whole turbocharger.
- What you may notice
- Check engine light on
- Loss of power or limp mode with reduced boost
- Often stored with actuator position or boost codes
- Likely causes
- LikelyElectronics or motor inside the actuator faulty
- PossibleSector gear or vane mechanism sticking (soot, coking), causing overcurrent
- PossibleWeak supply or ground, corroded connector
- RareSoftware of actuator or control module
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Hard · Usually a job for a workshop.Typical cost: €400 – €3,500
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.