P2AB9Wastegate Position Sensor A Circuit High
- Generic OBD-II code · Powertrain
- Turns on the check-engine light
- Matters for the ITP
- Can trigger limp mode
- How the car detects it
- P2AB9 is logged when the wastegate A position signal climbs above its valid ceiling. Typical reasons are a signal wire shorted to the sensor supply or to battery voltage, an open ground return that lets the input float upward, or an internal sensor fault. GM's ECM checks the raw position as a share of the reference: above 95 % in the 2019 L3B tables and above 99 % in the 2025 tables, each with 10 failures in 12 samples and Type A, lamp in the first trip. Ford flags it above 4.50 V for 4 s and has reflashed 2021-22 F-150 2.7L trucks (TSB 22-2357) as well as 2020-23 Explorer, 2022-23 F-150 3.5L and Expedition/Navigator (TSB 23-2353) against false settings. With the flap position unknown, boost is held back. P2AB8 is the low side, P2ABC bank 2.
- What you may notice
- Check engine light from the first trip
- Lower power under load, boost held back
- Powertrain fault (wrench) indicator on some Ford models
- Likely causes
- PossibleSignal wire shorted to the sensor supply or battery voltage
- PossibleOpen sensor ground or corroded ground terminal
- PossiblePCM calibration that sets the code falsely (Ford reflash for listed models)
- RarePosition sensor inside the electric actuator failed
- Inspection (ITP)
- Matters for the ITP. While the check-engine light is on, the car fails the emissions check.
- Repair
- Medium · Often possible to do yourself.Typical cost: €0 – €800
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.