P0850Powertrain
Park/neutral switch circuit malfunction
Where to start
The neutral safety switch circuit. A recognisable symptom: the car will not start in Park but starts in Neutral, or the other way round. Often it is not the switch but its adjustment after a repair — and adjustment is free.
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
We have a detailed piece on thisTransmission codes: P0700, P0715, P0720, P0741, P0750
How the code is built
Letter — the systemPowertrain: engine and transmission
Common or the maker's ownGeneric code: the same on every car
Which part of the engineTransmission and drivetrain
Number of the faultThe serial number inside that group — it does not say how serious the fault is
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.