P2128
Throttle/Pedal Position Sensor "E" Circuit High
Throttle/Pedal Position Sensor "E" Circuit High: the signal voltage is above the expected range. Often an open circuit or a short to supply voltage.
- 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.
- Signal wire shorted to supplyCommon
- Sensor ground openPossible
- Connector pins corroded - high contact resistanceLess likely
Parts involved
- Accelerator Pedal Sensor
- Accelerator Pedal Wiring
P2128 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.