OBD codes / P0220
P0220
SeriousThrottle/Pedal Position Sensor B Circuit
Take P0220 seriously — it commonly forces reduced-power mode and affects throttle response, which is a safety concern in traffic. It's usually drivable gently to a shop, but get it diagnosed promptly and don't rely on the car if acceleration is limited or unpredictable.
What this code means
Modern throttle and pedal assemblies use two sensors ('A' and 'B') that the computer cross-checks for safety. P0220 is a general fault in the 'B' throttle/pedal position sensor circuit. Common causes are a failed sensor, a wiring or connector fault, or — since the sensor is usually built into the electronic throttle body or accelerator pedal assembly — a failure of that whole unit. Because the throttle system depends on agreement between the two sensors, a fault here often forces reduced-power 'limp' mode.
Symptoms you might notice
- Reduced-power or 'limp' mode
- Hesitation or poor throttle response
- Rough idle or stalling
- Check-engine light, often with a warning light
What it costs to fix
Typical range: $60–$500 · about ~0.3–1.5 hrs of labor
| If the cause is… | Part | Labor |
|---|---|---|
| Accelerator pedal position sensor assembly | $50–$250 | ~0.3–1 hrs |
| Electronic throttle body | $150–$500 | ~0.5–1.5 hrs |
| Wiring / connector repair | $10–$120 | ~0.5–1.5 hrs |
Depends on whether the 'B' sensor lives in the pedal assembly or the throttle body — the pedal sensor is usually the cheaper of the two. A wiring/connector fix is inexpensive once found.
The price swings on which cause it turns out to be — so confirm the cause before paying. Diagnose P0220 for my exact vehicle →
How to fix P0220
Moderate — doable at home with common tools and patience
- Identify where sensor B lives on your vehicle
The 'B' throttle/pedal position sensor sits inside the electronic throttle body on some designs and inside the accelerator pedal assembly on others. Confirm which your car uses before diagnosing, because it decides which end of the system — and which replacement part — you're dealing with.
- Inspect that component's connector and harness
Check the relevant connector for corrosion, spread pins, and moisture, and the nearby harness for chafe. Since these sensors share a connector with their 'A' partner, a fault that hits only the B circuit often narrows to one damaged pin or wire.
- Compare the A and B signals through full travel
Graph both sensor voltages on a scan tool while sweeping the throttle or pedal slowly from closed to wide open. Sensor A tracking smoothly while B drops out, flatlines, or glitches confirms the B circuit fault and rules out a problem common to both.
- Verify the B circuit's reference and ground
The two sensors often run on separate reference circuits precisely so one failure can't take out both. Confirm sensor B's reference voltage and ground at the connector — a missing feed means a wiring or computer-side fault, not a bad sensor.
- Replace the pedal assembly or throttle body
The B sensor isn't sold separately: replace whichever unit houses it, then perform the relearn your vehicle calls for and confirm the limp mode clears. Pedal assemblies are the quicker, cheaper swap of the two.
DIY or shop? Connector checks and the A-versus-B comparison are very doable at home if your scanner graphs live data, and a pedal assembly swap is one of the easiest repairs on the whole throttle system. The throttle-body outcome costs more and often ends with a relearn that needs a capable scan tool, which is where many DIYers hand the last step to a shop. Because a B-sensor fault usually forces reduced power, treat the diagnosis as a driveway project on a parked car rather than something to chase between commutes.
Tools for the DIY steps: OBD2 scanner with live data graphing · Digital multimeter · Socket set and screwdrivers · Electrical contact cleaner · Dielectric grease
Not sure which step applies to your car? Get the likely cause for your exact vehicle before buying anything for P0220.
Frequently asked
Can I drive with P0220?
Cautiously and briefly. It often triggers reduced-power mode, which limits acceleration — risky in traffic. Drive gently to a shop if you must, and get it diagnosed promptly.
What is the 'B' throttle position sensor?
Throttle and pedal assemblies use two sensors the computer cross-checks for safety. The 'B' sensor is the second of that pair; P0220 is a fault in its circuit. The redundancy is why a single-sensor fault often triggers a protective limp mode.
Is P0220 the throttle body or the pedal?
Either — the 'B' sensor may be in the electronic throttle body or the accelerator pedal assembly depending on the vehicle. Diagnosis (and the wiring layout) determines which, and the pedal sensor is usually the cheaper fix.
How much does it cost to fix P0220?
Modest if it's the pedal sensor or wiring; more if it's the electronic throttle body. Diagnosis identifies which component carries the 'B' sensor before you buy parts.
Seeing P0220 on your car? Get a diagnosis specific to your exact year, make and model.
Diagnose P0220 for my vehicleRelated trouble codes
Don’t have a scanner yet? A ~$25 Bluetooth adapter reads codes like P0220 from your phone — see our honest guide to the best OBD2 Bluetooth adapters.
Generic OBD-II reference. Manufacturer-specific behavior varies — confirm with a scan tool and, for safety-related codes, a professional inspection.