P2123
PowertrainElectronic Throttlecritical severityThrottle/Pedal Position Sensor/Switch D Circuit High
What P2123 Means
High voltage from accelerator pedal position sensor D.
Symptoms
- Limp mode
- Unintended acceleration
- Check engine light
Common Causes
- Open ground circuit
- Short to voltage
- Failed sensor
Diagnostic Steps
- Measure voltage at APP sensor D
- Check for opens in ground
- Inspect wiring
Where to start: Replace pedal assembly or repair wiring.
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