Prevention is better than cure
If you are not comfortable spending too much on the maintenance and repair of your car, you can rely on car repair manuals. There is a repair manual available for download online that can help you in understanding the system of your car. This will help you in working with your car's batteries, its cables and connectors, as well as how BMW alternator and BMW starter work so that when they are down, you know how to fix it yourself.
With the help of your BMW repair manual, you will also get to know the proper use of a digital volt-ohmmeter or the DVOM, the ammeter, and the battery charger. Instructions are available on these repair car manuals on when it is needed for you to charge or not to charge your battery so as not to cause overcharging. There are also battery post cleaner tools which can enhance he performance of your batteries.
Treat your BMW like a baby
BMW cars are special in a sense that you should treat it like it's anything special. In fact, it should always be brought to the maintenance center or automotive dealers for regular tuning and check up. It is advised that the electrical system of your car should be put to test to avoid bigger problems.
Problems with voltage variations, which are the most usual problem for BMW cars, can be avoided if your car is regularly checked.
You can always rely to your do-it-yourself car repair manuals but then again, if your car is facing a more complicated problem, it is always best to consult from the repair center of BMW cars. Most BMW vehicles encounter problems with its electrical system and only electrical technicians of cars are good to solve such concerns. But then again, prevention is always better than cure. Take care of your BMW like it's the most prized possession you have.