P2125
Throttle/Pedal Position Sensor/Switch E Circuit
Throttle / pedal position
Generic OBD-II
Medium
What it means
P2125 indicates a circuit fault in the 'E' throttle/accelerator-pedal position sensor — the signal is out of the expected range or intermittent. Since the ECM uses this sensor to read throttle demand, the fault typically triggers reduced-power or limp mode until the sensor or its wiring is repaired.
Medium
Can I keep driving? Often limited — the car may drop into limp/reduced-power mode; drivable at low speed but have it fixed before relying on full throttle response.
Common symptoms
What you'll notice
- Check-engine light on
- Reduced engine power, often limp mode
- Hesitation or erratic throttle response
- Occasionally a hard start
Common causes
Most likely first
- Faulty accelerator pedal / throttle position sensor 'E'Likely
- Open or shorted sensor harness wiringCommon
- Poor or corroded electrical connection at the sensorCommon
- Faulty ECM/PCMLess often
How to diagnose & fix
Work through it in order
- Read freeze-frame and check for companion pedal/throttle codes (P2120, P2126, P2135).
- Inspect the sensor connector and harness for bent pins, corrosion, chafing, or a loose fit.
- With key on, engine off, verify a steady 5-volt reference and a good ground at the connector.
- Back-probe the signal wire and watch the voltage sweep smoothly as the pedal is moved.
- If reference, ground, and signal wiring are good, replace the pedal/throttle position sensor and retest.
FAQ
Quick answers
Is it safe to drive with P2125?+
Drivable at low speed, but the car may enter reduced-power mode and respond poorly to the throttle, so fix it before you need full power.
Can I just clear P2125?+
It will come back until the circuit fault is repaired — the ECM continuously monitors this sensor's circuit.
Related codes
Often seen with P2125
Read & clear P2125 yourself
Scan your car, confirm the code, and clear it once it's fixed — with OBD DashX on your phone.
✓ Verified name — SAE J2012 / ISO 15031-6Guidance reviewed by OBD DashX