CarScan
P2122Powertrain

Accelerator pedal sensor D — low signal

Where to start

A low signal from the first accelerator pedal sensor. The pedal has two, deliberately, so the unit can compare them. ⚠️ Start with the connector under the pedal: water off shoes and dirt off the mat get in there, and that is the commonest cause. A complete pedal assembly is expensive; the connector is free.

What to watch in live data

A code is not a diagnosis. It says which check failed, not which part to replace. Clearing it without repair only means the car will report it again in a few trips.

How to put together a report a mechanic will actually read

How the code is built

Letter — the systemPowertrain: engine and transmission
Common or the maker's ownGeneric code, second group
Which part of the engineFuel and air metering
Number of the faultThe serial number inside that group — it does not say how serious the fault is

All codes in «Throttle and accelerator pedal»

How it feels behind the wheel

The same fault shows itself in different ways. Each sign below says what to look at in the live data.

How the app helps

CarScan reads this code from your car through an OBD-II adapter, shows whether it is active now or only stored, names the module that reported it, and puts it into a plain-text report for your mechanic.

See what the app does

Unfamiliar word? Open the glossary

What the letter and the four digits mean