P0223 — Throttle/Pedal Position Sensor/Switch B Circuit High Input

Does P0223 always mean the throttle/pedal position sensor is bad?

No. P0223 can also result from an open B signal wire, a short to power, a poor ground, a damaged connector, or an ECU input-circuit problem.

What does “Circuit High Input” mean for P0223?

It means the ECU is receiving a voltage on the sensor/switch B signal line that exceeds its programmed high-input threshold.

Can I clear P0223 and continue driving?

Clearing the code does not repair the fault, and P0223 will usually return if the high voltage remains. The underlying circuit should be diagnosed before normal driving resumes.

Is it safe to drive a vehicle with P0223?

Use caution because inconsistent sensor B input can cause hesitation, surging, stalling, or limited throttle operation. Avoid aggressive driving and seek repair promptly.

When your vehicle's check engine light comes on and a scan tool pulls code P0223, the engine control module is telling you it has detected a problem with the throttle position sensor circuit — specifically, the signal voltage for sensor B is running higher than it should. In plain terms, the ECU is seeing a "circuit high" condition on the throttle/pedal position sensor switch B circuit, meaning the voltage is sitting near battery level instead of the expected lower range. This is not a reading the module can ignore; it indicates a genuine electrical fault that prevents the computer from accurately reading driver throttle input.

Modern engines rely on electronic throttle control, where the accelerator pedal commands a motor to open the throttle plate rather than using a mechanical cable. The throttle position sensors — typically two for redundancy — constantly feed voltage signals back to the ECU, which cross-checks them to confirm the plate is where it should be. When sensor B reports a voltage that spikes toward reference voltage (usually 5 volts) or battery voltage, the ECU flags P0223 because it cannot trust that reading anymore. The fault will not set on a single glitch; the module must observe the condition persist through its internal verification logic before illuminating the MIL (malfunction indicator lamp).

The specific freeze frame data stored alongside P0223 is your best starting point. That snapshot records engine load, RPM, coolant temperature, and vehicle speed at the exact moment the fault triggered. Reproducing those conditions during your diagnosis — rather than testing on a cold engine at idle — dramatically increases your chances of catching an intermittent problem. P0223 essentially means the throttle input circuit is misbehaving, and you need to trace whether the fault lives in the sensor itself, its ground reference, or somewhere in the wiring between the sensor and the ECU.

Symptoms of P0223

• Illuminated Check Engine Light
• Engine stalling or dying when coming to a stop
• Sluggish or non-responsive throttle pedal
• Vehicle enters limp-home (reduced power) mode
• Unstable, rough, or abnormally high idle speed
• Hesitation or stumble during acceleration

Common Causes

• Faulty throttle position sensor (sensor B) pulling the signal high
• Open or corroded ground circuit for the throttle position sensor
• Signal wire shorted directly to battery positive voltage
• Damaged wiring harness or loose/dirty connector in the throttle circuit
• Intake air leaks located downstream of the MAF sensor
• Carbon-fouled throttle body or a sticky throttle plate
• Contaminated or failing MAF or MAP sensor
• Failed electronic throttle motor assembly

How to Diagnose P0223

1. Connect an OBD2 scanner and confirm P0223 is stored in the ECU. Record the freeze frame data — this tells you engine load, RPM, temperature, and speed at the moment of failure, so you can recreate those conditions during testing.

2. Pull any other stored codes. P0223 often accompanies related throttle or intake codes, and manufacturer TSBs (technical service bulletins) may have a known fix or software update for your specific model. Search by VIN on the manufacturer website or NHTSA.gov.

3. Visually inspect the throttle position sensor harness and connectors for frayed wires, chafing, corrosion, or pins that are bent, pushed out, or water-damaged. Pay special attention to areas near the throttle body where heat and vibration cause wear.

4. With the sensor disconnected, probe the signal wire at the harness connector with a multimeter. If you still read high voltage (near 5V or battery voltage) with the sensor unplugged, you have a short-to-power in the wiring. If the voltage drops to normal reference range, the sensor itself is the culprit.

5. Inspect and manually cycle the throttle plate — it should move freely with no binding or flat spots. Carbon buildup is common and can be cleaned. While the throttle is disconnected, monitor live data for the position sensor readings as you slowly open the plate by hand; they should sweep smoothly from low to high with no jumps or drops.

6. Clear the code, complete a drive cycle that reproduces the freeze frame conditions (hard acceleration, specific temperature range, etc.), and verify P0223 does not return.

Repair Options and Costs

• Replace throttle body assembly (includes sensor): $250–$700
• Clean throttle body (labor and solvent): $80–$200
• Replace MAF or MAP sensor: $150–$400

Total Repair Cost for P0223

The final bill depends entirely on which component is actually at fault. A throttle body cleaning at $80–$200 is by far the most common and cheapest fix, and it resolves the issue in many cases. If the throttle body motor or integrated sensor has failed, replacement runs $250–$700 depending on make, model, and whether you use OEM or aftermarket parts. A bad MAF sensor adds $150–$400 to the estimate. Most shops will charge one to two hours of labor on top of parts. Bottom line: expect to pay somewhere between $80 and $700 total for a proper repair.

Can You Drive with P0223?

Drive with caution. When P0223 sets, many vehicles respond by dropping into limp-home mode, limiting engine power to roughly 30–50 percent. This is enough to safely coast to a repair facility, but it is not a condition you want to maintain on the highway or in heavy traffic. If the throttle becomes unresponsive, the engine stalls repeatedly, or the car lurches unexpectedly, stop driving immediately and have it towed. Treat P0223 as a signal that your throttle input is no longer being read reliably — get it diagnosed before it leaves you stranded.

Related OBD2 Codes

• P0200: Injector Circuit Malfunction
• P0201: Injector Circuit Malfunction - Cylinder 1
• P0202: Injector Circuit Malfunction - Cylinder 2
• P0203: Injector Circuit Malfunction - Cylinder 3
• P0204: Injector Circuit Malfunction - Cylinder 4
• P0205: Injector Circuit Malfunction - Cylinder 5