The P2120: Throttle/Pedal Position Sensor/Switch ‘D’ Circuit refers to an issue in the electrical circuit for the throttle or pedal position sensor ‘D’. This could be due to a faulty sensor, an open or short in the wiring, or problems with the sensor connector.
P2120 – Quick Overview
Code | Information |
---|---|
Meaning | P2120: Throttle/Pedal Position Sensor/Switch ‘D’ Circuit |
Is it serious? | Yes, it can affect throttle response and cause drivability issues. |
Possible causes | – Faulty throttle/pedal position sensor ‘D’ – Open or short circuit in the sensor wiring – Issues with the sensor connector |
How to diagnose? | – Inspect the wiring and connector for the throttle/pedal position sensor ‘D’ – Test the sensor for proper operation – Check for open or short circuits in the sensor circuit |
P2120 Meaning
The P2120 code points to an electrical problem with the throttle or pedal position sensor ‘D’. This sensor is crucial for the vehicle to monitor throttle position and respond to the driver’s input. A faulty sensor or a wiring issue can prevent the throttle from responding properly, leading to poor acceleration or performance issues.
Step-by-step diagnostic guide
Action | Description | Tools Needed |
---|---|---|
Check for Other Codes | Use an OBD-II scanner to check if there are any other related codes that could provide more insight into the issue. | OBD-II Scanner |
Inspect Throttle/Pedal Sensor Wiring | Visually inspect the wiring and connectors for the throttle/pedal position sensor ‘D’ for any signs of damage, loose connections, or corrosion. | Flashlight, Multimeter |
Test Sensor Operation | Use a multimeter to test the throttle/pedal position sensor ‘D’ for proper functionality. Compare the readings to manufacturer specifications. | Multimeter |
Check for Open or Short Circuits | Perform a continuity test on the throttle/pedal position sensor ‘D’ circuit to check for any open or short circuits. | Multimeter, Wiring Diagram |
Inspect and Clean Connectors | Ensure the sensor connectors are clean, secure, and free of corrosion or debris. Clean or replace as necessary. | Contact Cleaner, Flashlight |
Clear the Code and Test Drive | After repairs or adjustments, clear the code using an OBD-II scanner and take the vehicle for a test drive to ensure the issue has been resolved. | OBD-II Scanner |
Recheck for Codes | Re-scan the vehicle after the test drive to ensure the P2120 code does not return. | OBD-II Scanner |

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Hi, I am Juraj “Yuri” Lukacko. I got frustrated by unhelpful and scammy mechanics, so I decided to learn everything about car diagnostics myself. I test dozens of new car diagnostic tools every month along with learning new strategies to fix and customize cars. About Juraj Lukacko (Yuri)