P0221Throttle/Pedal Position Sensor/Switch B Circuit Range/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
- With electronic throttle control the throttle body carries two position sensors, A and B, usually with opposite or offset signals, and the engine module compares them (correlation code P2135). GM and Ford give the pedal sensors their own codes (P2120 ff), so B is in practice the second throttle sensor. P0221 is the plausibility fault: the signal of sensor B is electrically valid but does not match sensor A or the throttle position expected from airflow. Bosch ME9 engines (Saab) set it at a deviation of more than 9 %, older Ford systems at more than 7 degrees between the sensors without the warning light; many newer engines report this only as P2135. The module carries on with sensor A, limits throttle opening and power and switches off cruise control.
- What you may notice
- Check engine light on
- Limp mode, reduced power
- Rough idle, jerking
- Cruise control disabled
- Likely causes
- LikelyWorn track of sensor B (signal jumps)
- PossibleContact resistance at connector or wiring
- PossibleThrottle dirty or sticking
- RareMass airflow sensor fault or false air
- 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: €80 – €600
- Related codes
Explanation from obdex (CC0), exactly as the app shows it. Guidance only; confirm with a workshop.