Volkswagen Golf/Jetta/Cabriole 1990-1999
Always disconnect the battery cables when removing or disconnecting the alternator.
Disconnect the battery cables before using a fast charger. The charger has a tendency to force current "backwards" through the diodes and burn them out.
Never disconnect the battery cables or alternator while the engine is running.
Do not attempt to "polarize" an alternator.
Never reverse battery connections. Do not connect the battery in series with another without disconnecting it from the charging system.
When jump starting from another vehicle, try to avoid running the other car's engine. Do not allow alternators from two different charging systems to be running and connected with jumper cables.
Do not ground the alternator output terminal.
Disconnect the battery cables before using an electric arc welder on the car.