Powertrain
Generic/SAE
OBD-II Fault Code
P0221: Throttle/Petal Position Sensor/Switch B Circuit Range/Performance Problem
Meaning, symptoms, likely causes, diagnostic checks and repair guidance for P0221.
Throttle / pedal sensor
Use this category to narrow your checks before replacing parts.
High
Severity is a general guide. Confirm with scan-tool data and vehicle symptoms.
What P0221 usually means
Throttle/Petal Position Sensor/Switch B Circuit Range/Performance Problem.
Common symptoms
Check Engine light; Poor drivability or reduced fuel economy depending on fault; Reduced power / limp mode possible; Hesitation or unstable idle
Likely causes
Dirty throttle body; Faulty throttle/pedal position sensor; Wiring/connector fault; Adaptation needed; Signal out of expected range; Mechanical issue affecting sensor reading; Slow/sticking actuator
Diagnostic checks
Scan all modules and record freeze-frame data before clearing codes; Check battery voltage and related fuses; Inspect throttle body and connector; Check sensor correlation data with scan tool; Compare live data to expected value and inspect mechanical operation
Repair guidance
Clean throttle body if appropriate, repair wiring, perform throttle relearn, replace failed sensor/body after testing; Repair mechanical cause, clean/replace sticking actuator, or replace sensor after confirmation
Verification after repair
Clear code, road-test through the same drive condition, then rescan