P2122
Throttle/Pedal Position Sensor "D" Circuit Low
Throttle/Pedal Position Sensor "D" Circuit Low: the signal voltage is below the expected range. Often a short to ground or high resistance in the wiring.
- Check engine light: Yes
- Emissions related: Yes
- Repair difficulty: easy
Symptoms
- Check engine light on
- Reduced throttle response, possible limp mode
- Hesitation or surging
- Idle too high or too low
Common causes
Ordered by how often each turns out to be the cause.
- Pedal sensor track wornCommon
- Signal wire shorted to groundPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Accelerator Pedal Sensor
- Accelerator Pedal Wiring
P2122 is a generic OBD-II code defined by SAE J2012. Exact wording and diagnostic procedure vary by manufacturer and model. Code definitions are drawn from the public-domain OBDex dataset; the workshop notes are our own.