P2122: Throttle/Pedal Position Sensor/Switch D Circuit Low
Do not keep driving
Expect reduced power or no throttle response. If the footwell has ever been wet — a leaking screen seal, a blocked pollen filter drain, a spilled drink — mention it, because moisture in the pedal connector produces exactly this and drying and cleaning it may be the whole repair.
What this code means
Sensor D reads below its valid range, normally a short to ground. The module treats an implausibly low pedal signal as untrustworthy rather than as a released pedal — which is the correct choice, since acting on it would mean ignoring a driver who may well be asking for power.
Water is the cause to suspect first on a pedal sensor. A connector that has been wet reads low long before it reads open, because moisture provides a leakage path to ground that is not quite a short.
Likely causes
Start here
- Water ingress into the footwell · moderate
- Corroded accelerator pedal connector · easy
- Wiring shorted to ground · moderate
Less common
Symptoms
Components involved
Information, not instruction
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Community experience
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