P0228: Throttle/Pedal Position Sensor C Circuit High (Meaning, Causes, Fixes)
What P0228 means
On drive-by-wire vehicles there is no throttle cable. The powertrain control module (PCM) reads one or more accelerator pedal position sensors (PPS) and several throttle position sensors (TPS) on the throttle body, and moves the throttle with an actuator motor. OBD-Codes.com explains that most of these sensors are potentiometers fed a reference voltage (typically 5 volts) and a ground, with signal voltage changing as the pedal or throttle plate moves. If the signal voltage on circuit 'C' stays above a programmed limit for long enough under certain conditions, the PCM stores P0228 and may turn on the check engine light. RepairPal describes the same sensors (the TPS on the throttle body and the pedal sensor in the accelerator pedal assembly) and says the PCM sets P0228 when it detects a problem with the sensor or its circuit. Which sensor counts as 'C' depends on the vehicle, so check its service information. Searches for this code mention Chevy, Infiniti, Nissan, Ford, Peugeot and VW TDI.
Severity: can I keep driving?
Stop and fix promptly
Fix it now. RepairPal rates P0228 'Urgent' and says the engine computer may limit the vehicle to about 20 mph in limp home mode. OBD-Codes.com says the PCM usually enters limp mode, acceleration can be severely limited or disabled, and the throttle can stick or the engine can stall at idle, so it may not be safe to drive in traffic.
Common symptoms
- Check engine light on (both sources)
- Limp home mode with reduced engine performance; RepairPal says speed may be limited to 20 mph or less (both sources)
- Limited or no acceleration, or hesitation when accelerating (OBD-Codes.com)
- Stuck throttle at any RPM (OBD-Codes.com)
- Engine stalls when allowed to idle (OBD-Codes.com)
- Cruise control not working (OBD-Codes.com)
- Increased fuel consumption (RepairPal)
Likely causes
Roughly most to least common, based on the sources below. Your vehicle may differ.
- Defective throttle position sensor (both sources)
- Failed pedal position sensor or accelerator pedal assembly (both sources)
- Open or shorted wiring between the sensors and the PCM (both sources)
- Corroded electrical connectors (OBD-Codes.com)
- Faulty drive-by-wire throttle actuator motor (OBD-Codes.com)
- Heavy carbon buildup holding the throttle plate open at startup (OBD-Codes.com)
- PCM failure (RepairPal)
Diagnostic steps you can do
Work on a cool engine, parked on level ground with the parking brake set. Never work under a car supported only by a jack.
- Check for technical service bulletins for your year, make and model first, since the issue may be known with a known fix.
- Look over the wiring and connectors at the throttle body and the accelerator pedal for damage, loose pins or corrosion.
- With the engine off, look inside the throttle body for carbon buildup or damage. OBD-Codes.com says heavy carbon that holds the throttle open at startup can set this code; clean it following the manufacturer's procedure.
- Read and write down all stored codes and freeze frame data, clear them and test drive to see if P0228 returns.
- If the car is in limp mode, has a stuck throttle or stalls, don't drive it in traffic; have it diagnosed.
Typical fixes
- Repair or replace damaged wiring or corroded connectors
- Clean carbon from the throttle body per the manufacturer's recommendations
- Replace the faulty throttle position sensor or throttle body
- Replace the accelerator pedal position sensor / pedal assembly
- Replace a faulty drive-by-wire throttle actuator motor
- Repair or replace the PCM only after other causes are ruled out (RepairPal lists PCM failure)
Repair costs vary widely by vehicle, region, parts brand and shop, so we don't quote prices. Get a written estimate after diagnosis.
🛠 When to call a pro
- OBD-Codes.com: watch TPS and PPS data on a scanner (narrowed to the relevant data for faster response) for voltage spikes or disagreement between sensors. If none show, back-probe each sensor's signal and ground with a DVOM or oscilloscope and move the throttle slowly from closed to wide open, looking for spikes or dropouts. Voltage usually ranges from about 0.5 V closed to 4.5 V wide open; check the vehicle's own spec.
- OBD-Codes.com notes that some manufacturers require replacing the throttle body, throttle actuator motor and all throttle position sensors together.
- The sources differ in emphasis: OBD-Codes.com lists wiring, sensors, connectors, the actuator motor and carbon buildup, and does not name the PCM; RepairPal lists the pedal assembly, PCM, TPS and wiring, and adds increased fuel consumption as a symptom.
Where to buy
Plain search links. Always match parts to your exact year, make, model and engine.
FAQs
Can I drive with P0228?
It's not a good idea. RepairPal rates it 'Urgent' and says the car may be limited to 20 mph or less, and OBD-Codes.com lists a stuck throttle and stalling at idle. Get it diagnosed before driving in traffic.
Is P0228 a throttle sensor or a gas pedal sensor problem?
It can be either. The 'C' circuit can belong to a throttle position sensor or a pedal position sensor depending on the vehicle, so check the service information for yours.
Can a dirty throttle body cause P0228?
OBD-Codes.com says excessive carbon buildup that holds the throttle body open at startup can cause it, so inspecting and cleaning the throttle body is part of the diagnosis.
What is the difference between P0227 and P0228?
Both are for throttle/pedal position sensor 'C'. P0227 means the circuit voltage is too low and P0228 means it is too high, per RepairPal's code list.
Sources
Last reviewed 2026-10-26. Code definitions and repair steps can vary by manufacturer. Confirm with your vehicle's service information.