I have a 2003 325xi that I bought in November last year(2007). My battery went out a week ago while driving. I did have a problem with it not starting the day before but I could jump it and everything was fine. The next day, a bunch of strange things started happening while driving. (brake light, battery light, warning light where all flickering) Soon after that the car hesitated then died. I replaced the battery but the "red" battery light is still on and when I rev the engine the radio lights dim. Any ideas? Thanks in advance.
have someone test the alternator and voltage regulator (assuming your car has a voltage regulator, I wouldn't know offhand) and see if it's charging the battery?
And the answer is....... It was the alternator. I had it changed and everything is good now($$$). While all this strange stuff was happening, both my high beams went out at the same time. I figure this might be because of the fluctuating current. (They were fine before this all started.) By the way, I'm glad I got a discount with the Club membership!
Just a FWIW, modern BMWs don't like jump starting very well. Fried electronics due to jumping are common.
Especially if you connect both cables to the battery on the receiving car. The ground cable should go to engine block etc.
