P2120Throttle Actuator Control
Pedal Position Sensor / Switch D Circuit
P2120 means the ECM detected a general fault in the accelerator pedal position sensor D circuit, such as an open, short, or out-of-range signal.
🚗 Not recommended. A pedal sensor circuit fault can force limp mode.
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🎯 Top Causes, Ranked by Likelihood
#1Failed accelerator pedal position sensor$100-$400
A worn or failed sensor element is the most common cause.
#2Wiring or connector fault at the pedal$50-$300
Open, shorted, or corroded wiring disrupts the circuit.
#3Poor 5V reference or ground$50-$300
A bad reference or ground skews the signal.
#4Faulty ECM$200-$1200
An internal ECM fault misreads the sensor.
🩺 Common Symptoms
- Reduced power / limp mode
- Check engine light
- Poor throttle response
- Hesitation
- Erratic idle
💰 Repair Cost: DIY vs Shop
📋 Free OBD2 Code Cheat Sheet
The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.
🔧 How to Diagnose P2120
1Read live data for the pedal position sensor D circuit
2Inspect the pedal connector and wiring
3Test the 5V reference and ground
4Replace the pedal position sensor if faulty
❓ Frequently Asked Questions
Can I drive with a P2120 code?
Avoid it. Pedal sensor circuit faults commonly force limp mode.
How much does it cost to fix P2120?
A pedal position sensor replacement typically runs $150-$600 at a shop.
What causes P2120?
Usually a failed pedal position sensor or a wiring fault in the D circuit.
🔗 Related Codes
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