Worn or contaminated throttle pedal position sensor 'C' track inside the pedal assembly.; Chafed, pinched or corroded wiring in the sensor 'C' circuit, often near the pedal or firewall.; Loose or backed-out terminal pins at the sensor connector or engine computer.; Water or oil intrusion into the pedal sensor connector causing intermittent contact.; A failing throttle body actuator or position sensor on electronic throttle vehicles.; Rarely, an intermittent internal fault in the engine control module (ECM).

DTC codes / P02xx · Fuel and air metering (injector circuits) / P0229

P0229Throttle/Pedal Position Sensor/Switch 'C' Circuit Intermittent

P0229 means the engine computer detected an intermittent signal from the throttle or pedal position sensor circuit designated 'C'. The circuit works most of the time but drops out or glitches momentarily, so the computer cannot trust the throttle position reading and sets this code.

SystemPowertrain

Code typeGeneric (all makes)

SeverityMedium

Fix difficultyIntermediate

AreaFuel and air metering (injector circuits)

Symptoms you may notice

Often no symptoms besides the warning light, especially if the glitch is brief.
A momentary stumble or hesitation when accelerating from a stop.
The engine may enter limp mode or limit power intermittently.
Poor or delayed throttle response that comes and goes.
An unstable or surging idle when the pedal is released.
Cruise control may disengage or refuse to set.

Common causes, most likely first

Worn or contaminated throttle pedal position sensor 'C' track inside the pedal assembly.
Chafed, pinched or corroded wiring in the sensor 'C' circuit, often near the pedal or firewall.
Loose or backed-out terminal pins at the sensor connector or engine computer.
Water or oil intrusion into the pedal sensor connector causing intermittent contact.
A failing throttle body actuator or position sensor on electronic throttle vehicles.
Rarely, an intermittent internal fault in the engine control module (ECM).

How to diagnose and fix it

Scan all modules and record freeze-frame data to see when the intermittent fault occurs.
Inspect the pedal sensor connector and wiring for corrosion, chafing or loose pins.
Wiggle-test the harness while watching live throttle position data for dropouts.
Check sensor reference voltage and ground at the connector with a multimeter.
Compare sensor 'C' voltage sweep against the other throttle position sensors for consistency.
Replace the faulty pedal assembly or repair the damaged section of harness.
Clear the code and road-test with a scan tool recording to confirm the repair.

Intermittent faults hide in connectors and harnesses

A sensor that tests perfectly on a stationary vehicle can still set P0229 because the fault only appears under vibration or heat; always wiggle-test the harness while watching live data.
Many vehicles use redundant throttle position sensors, and a glitch in only one track may not cause a noticeable driveability symptom, so the warning light is the only clue.
Corroded terminals at the pedal connector are a more common cause than a failed pedal assembly, so inspect and clean the pins before replacing parts.
Aftermarket floor mats or debris jammed behind the pedal can stress the sensor wiring and create an intermittent signal that mimics a sensor failure.
P0229 can be set by a low battery or charging system glitch that momentarily drops sensor reference voltage, so check battery health and grounds before condemning the sensor.

Can I keep driving with P0229?

You can usually drive carefully to a repair shop, but avoid heavy acceleration and be ready for the engine to enter limp mode. If the throttle response becomes unpredictable or the engine repeatedly cuts power, stop driving and have it towed.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.