P0228 Throttle/Pedal Position Sensor/Switch C Circuit High Input

P0228 points to throttle or pedal position sensor C circuit high. The C signal is open, shorted to voltage, or above expected range.

Code details

Generic OBD-II · P0

System: Fuel / Air
Code type: Generic (SAE / ISO controlled)
Standard: SAE J2012 / ISO 15031-6

Diagnostic boundary

A diagnostic trouble code reports that a monitored test failed. It does not prove one specific part is bad, and manufacturer logic can add vehicle-specific conditions.

Do not assume a commanded throttle fault until the high sensor C signal path is isolated.

Symptoms of P0228

Check-engine light on, sometimes with rough or uneven running.
Hesitation, surging, or a noticeable change in fuel economy.
Occasionally hard starting or a smell of unburnt fuel.

Common causes of P0228

A failing or contaminated sensor (MAF, MAP, oxygen or air-fuel sensor).
Intake or vacuum leaks, or an exhaust leak near an upstream sensor.
Wiring, connector, or fuel-delivery problems that skew the reading.

Useful checks before replacing parts

Check sensor C signal voltage, ground path, open circuits, short-to-voltage faults, connector fit, and reference voltage.
Compare sensor C with redundant pedal or throttle tracks while sweeping through the range and monitoring correlation.
Inspect water intrusion, connector corrosion, wire strain, and harness damage near the pedal or throttle body.

Related OBD-II codes

These nearby fuel / air entries can help compare wording and pin down the fault area.