P2122 indicates that the voltage signal from the throttle pedal position sensor's switch D circuit is lower than expected. The PCM detects an abnormal low input from this sensor.
The sensor may have an internal open or short that produces a low voltage signal.
Corroded terminals, broken wires, or a loose plug can interrupt the signal and lower voltage.
Vibration or movement can cause momentary loss of contact, triggering the low-input condition.
The entire sensor module can malfunction, affecting multiple switch circuits including D.
A rare PCM issue with the sensor's input circuit can mimic a low-voltage condition.
It is uncommon; the code is usually due to a faulty sensor, wiring, or connector rather than the PCM itself.
Only if the sensor inside the assembly is defective; often the wiring or connector can be repaired instead.
Yes, after the underlying issue is fixed and the code is cleared, the light will remain off.
It depends on the specific fault, but many fixes can be completed in under an hour.