981 · Engine

P2122

Throttle/Pedal Position Sensor/Switch "D" Circuit Low Input

HIGH SEVERITY

Accelerator pedal position sensor "D" circuit voltage low.

SYMPTOMS

  • Check-engine light
  • Drivability or performance issues

LIKELY CAUSES

  • Faulty accelerator pedal position sensor
  • Short to ground in the signal wire
  • Open ground or corroded connector
  • ECM/PCM fault (rare)

DIAGNOSIS STEPS

  • Inspect the accelerator pedal position sensor wiring and connector
  • Check the signal circuit for a short to ground
  • Verify reference voltage and ground
  • Compare live data to expected
  • Replace the component if confirmed faulty

RELATED PARTS

  • Accelerator pedal sensor
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