P0625Powertrain
Generator field terminal — low signal
Where to start
A low signal in the alternator field circuit. The same steps as P0622, but here worn brushes and the regulator are more common — a part replaced separately from the alternator and costing far less.
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 thisCharging and voltage: P0560, P0561, P0620, P0621, P0622
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 engineControl module and its circuits
Number of the faultThe serial number inside that group — it does not say how serious the fault is
All codes in «Control module and its circuits»
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.