P0120: Throttle/Pedal Position Sensor/Switch A Circuit Malfunction
Can you still drive? Driving is not recommended. The vehicle may enter limp mode or behave unpredictably. Have it towed or drive directly to a repair shop.
What Does P0120 Mean?
Code P0120 indicates a general malfunction in the throttle position sensor (TPS) circuit. The ECU cannot receive a reliable signal indicating how far the throttle is open. This is critical because the TPS signal directly affects fuel injection, ignition timing, and transmission shifting. Driving with this code can be unpredictable.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonCommon Causes
- Faulty throttle position sensor
- Damaged TPS wiring or connector
- Worn throttle body
- Carbon buildup on throttle plate affecting sensor
Symptoms
- Check engine light on
- Erratic or surging idle
- Hesitation or stumbling on acceleration
- Vehicle may enter limp mode
- Transmission shifting problems
Diagnostic Steps
- 1Read and document freeze frame data
- 2Check TPS voltage at closed throttle, half throttle, and wide-open throttle
- 3Inspect TPS connector and wiring for damage
- 4Look for dead spots in the TPS signal by slowly opening the throttle while monitoring voltage
- 5Clean the throttle body and check again
- 6Replace TPS if voltage output is erratic or out of range
Recommended Parts & Tools
throttle position sensor
throttle body cleaner
Estimated Repair Cost
| Type | Estimated Cost |
|---|---|
| Total Repair Cost Range | $50 - $400 |
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Chat with AI About P0120Commonly Affected Vehicles
Related Recalls
1 Active Recall — 2026 Ford F-150
The following NHTSA safety recalls have been issued for this vehicle. Contact your dealer to check if your vehicle is affected.
ELECTRICAL SYSTEM: INTEGRATED TRAILER BRAKE CONTROL
Ford Motor Company (Ford) is recalling certain 2021-2026 F-150, 2022-2026 F-250 SD, F-350 SD, F-450 SD, F-550 SD, Maverick, 2024-2026 Ranger, 2023-2026 F-600 SD, 2022-2027 Lincoln Navigator, Expedition, and 2026 E-Transit vehicles. When towing a trailer, the integrated trailer module (ITRM) may lose communication with the vehicle, possibly causing a loss of brake and turn signal lights, or a loss of brake function. As such, these vehicles fail to comply with the requirements of Federal Motor Vehicle Safety Standard number 108, " Lamps, Reflective Devices, and Associated Equipment."
Remedy: The integrated trailer module software will be updated by a dealer, or through an over-the-air (OTA) update, free of charge. Owner notification letters are expected to be mailed March 17, 2026. Owners may contact Ford customer service at 1-866-436-7332. Ford's number for this recall is 26C10. Vehicle Identification Numbers (VINs) involved in this recall will be searchable on NHTSA.gov beginning March 17, 2026.
Data provided by the National Highway Traffic Safety Administration (NHTSA).
Frequently Asked Questions
What is limp mode?
Limp mode is a safety feature that limits engine power and speed when the ECU detects a critical sensor failure like TPS malfunction. It allows you to drive slowly to a repair shop but prevents normal driving.
Can I drive with P0120?
It is not recommended. The throttle may respond unpredictably, making driving unsafe. If the vehicle enters limp mode, drive directly to a mechanic at reduced speed.
Community Fix Reports
Community reports are user-submitted and not verified by Auto AI Buddy. Results may vary.
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