Skip the auto shop - Our mechanics make house calls

P2125 OBD-II Trouble Code: Throttle/Pedal Position Sensor/Switch "E" Circuit

Check Engine Light

P2125 code definition

P2125 is a general OBD-II trouble code indicating a fault with the throttle/pedal position sensor/switch “E” circuit. This code is similar to many other throttle body and pedal position codes.

What the P2125 code means

The engine control module (ECM) uses the signals from the throttle body and position sensor to command the throttle body actuator motor to open the throttle plate. This allows air into the engine and is varied by how hard the pedal is pressed and how far.

This code will only be seen on cars with a drive-by-wire or an electronically controlled throttle body. Once the ECM detects a fault with the sensor or switch circuit “E” the P2125 code is set, and this causes a Check Engine Light to be displayed on the dashboard. With the Check Engine Light, the ECM puts the vehicle into a failsafe mode to prevent any further damage to the vehicle.

What causes the P2125 code?

Many different components can cause the P2125 code:

  • Open or short in the wiring harness
  • Failed throttle actuator control motor
  • Throttle position sensor that has failed
  • Failed pedal position sensor
  • Poor electrical connection

What are the symptoms of the P2125 code?

Symptoms can sometimes be felt before the Check Engine Light is displayed on the dashboard. A wide range of symptoms are seen with the P2125 code such as:

  • Check Engine Light illuminated on the dash
  • The vehicle may not move when the gas pedal is depressed
  • Engine may exhibit a misfire condition
  • Vehicle may run poorly

How does a mechanic diagnose the P2125 code?

Mechanics will follow these simple steps when performing diagnosis of the P2125 code:

  • Using a scan tool to check the ECM for any stored codes including history and pending codes

  • Noting all codes that are present as well as the freeze frame data associated with each code

  • Clearing all codes for a clean slate

  • Performing a test drive of the vehicle attempting to duplicate the conditions found in the freeze frame data

  • Conducting a visual inspection to look for any damaged components, worn or broken wires, and broken parts

  • Using the scan tool and its datastream to watch the sensor “E” while the throttle and gas pedal are operated. There should be changes in the values if they are working properly.

  • Finally, a multimeter will be used to check that voltage is present at the sensor and for continuity

Common mistakes when diagnosing the P2125 code

Mistakes can be made with any code if steps are not followed in the proper order or skipped entirely. Overlooking simple steps can lead to the wrong components being replaced which wastes both time and money.

How serious is the P2125 code?

P2125 can have some rather serious symptoms. If the ECM can’t detect the signal from the throttle/pedal switch, it may not allow the throttle to work at all. If this occurs, the vehicle will not move at all when the gas pedal is depressed. If drivability problems are present, the vehicle should not be driven and should be repaired as soon as possible.

What repairs can fix the P2125 code?

The most common repairs of the P2125 code are:

Additional comments for consideration regarding the P2125 code

An advanced-level scan tool goes a long way towards helping diagnose the P2125 code. These tools give technicians access to advanced features in the ECM with the most helpful being the ECM’s live data stream. This tool shows sensor and solenoid data, and allows the mechanic to monitor operation and note changes over time.

Need help with a P2125 code?

YourMechanic offers certified mobile mechanics who will come to your home or office to diagnose and repair your vehicle. Get a quote and book an appointment online or speak to a service advisor at 1-800-701-6230.

The statements expressed above are only for informational purposes and should be independently verified. Please see our terms of service for more details
Icon-warranty_badge-02

Skip the repair shop, our top-rated mechanics come to you.

At your home or office

Choose from 600+ repair, maintenance & diagnostic services. Our top-rated mechanics bring all parts & tools to your location.

Fair & transparent pricing

See labor & parts costs upfront, so you can book with confidence.

12-month, 12,000-mile warranty

Our services are backed by a 12-month, 12,000-mile warranty for your peace of mind.

Get A Quote

Need Help With Your Car?

Our certified mobile mechanics make house calls in over 2,000 U.S. cities. Fast, free online quotes for your car repair.

GET A QUOTE

Post a question and get free advice from our certified mechanics.

ASK A QUESTION

More related articles

How to Avoid Back Pain in a Car
If you have back problems, sitting in a car for an extended period of time can be excruciating. Even without back problems, you could experience discomfort and soreness from...
P2159 OBD-II Trouble Code: Vehicle Speed Sensor B Range/Performance
Diagnostic Trouble Code (DTC): P2159 P2159 code definition Vehicle Speed Sensor B Range/Performance Related Trouble Codes: P2158: Vehicle Speed Sensor B P2160: Vehicle Speed Sensor B Circuit Low P2161:...
P2422 OBD-II Trouble Code: Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed
Diagnostic Trouble Code (DTC): P2422 P2422 code definition Evaporative Emissions Control System (EVAP) Vent Valve Stuck Closed Related Trouble Codes: P2441: EVAP Vent Valve Stuck Open EVAP trouble...


Related questions

Q: Check engine light

Wow... 329,000 miles on your Chevrolet Uplander. Assuming you are still on your original engine, that is a long lived vehicle. If your Check Engine Light is on, YourMechanic will use an electronic code retrieval tool to download the DTC's...

Q: I just got the car two days ago and the engine light is on

Hey there, thanks for writing in about your 2010 Cadillac CTS. The light coming on may mean that they just cleared the code and light before selling you the car, or your light is on from a loose gas cap....

Q: Tranny troubles

You need to have the transmission leak from the bell housing fixed. The fluid leaking is causing the transmission shift problem. The trouble code P2271 indicates that the O2 sensor after the converter shorted rich. This may happen if transmission...