P0229 Throttle/Pedal Position Sensor/Switch C Circuit Intermittent

P0229 indicates an intermittent throttle or pedal position sensor C circuit fault. The C signal drops out, spikes, or becomes invalid sometimes.

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 clear intermittent throttle codes without stressing the circuit and confirming stable redundant-track correlation.

Symptoms of P0229

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 P0229

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

Graph sensor C alongside redundant tracks during pedal sweep, road vibration, heat soak, and connector movement.
Inspect terminal tension, connector locking, water intrusion, harness flex points, shared reference stability, and sensor track wear.
Compare signal interruptions with reduced-power mode, throttle command, idle changes, and freeze-frame conditions.

Related OBD-II codes

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