P2126
Throttle/Pedal Position Sensor "C" Circuit Intermittent
The "C" channel produces an intermittent signal — usually a marginal connector or a worn track inside the pedal sensor.
- 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.
- Connector intermittentCommon
- Track C worn at common pedal anglePossible
- Harness routed against vibrating componentLess likely
Parts involved
- Accelerator Pedal Sensor
- Pedal Sensor Wiring
P2126 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.