All those luxurious extras you have on your BMW have to get their electricity from somewhere. Think it's the battery? Nope. Your BMW Alternator is the source of power for pretty much everything in your car that uses electricity. The alternator is a mini-generator that develops AC power, and it's driven off a belt by the engine. And it's not just your heated seats and iDrive system that's powered by the alternator: a healthy BMW alternator also keeps your battery charged up for those cold morning starts.

If your battery has seemed sluggish lately, or you've had the battery warning light on your dash illuminate, get your BMW alternator checked out. It's a fairly simple procedure, and a good shop can test for both voltage and output--you can have good readings for one but not the other on a failing alternator. After all, you don't want a bad BMW alternator to leave you stranded at an inopportune time. More than your heated seats are at stake!