replaced alternator, however abs light, traction control light, and parking brake
ok so i recently bought my 2002 BMW 745i and i love it it really is a nice luxury car.
However shortly after buying it, i was driving for a while, i was in the middle of a 2 hour trip when all of the sudden the abs, traction control, and parking brake light went on.. shortly after this the speakers started cutting out.. then next thing i know there are a ton of different dummy lights popping up in my face including "transmission failsafe" i pull over and turn the car off, and it wouldn't start back up.
shortly after this incident i came to the conclusion that it was either my battery or alternator. after replacing the battery, the same thing happened. I then had a parts store test the alternator and it was bad. i was able to find a cheap part and a cheap yet good mechanic and to make a very long story short i got the alternator replaced.
however after driving it home from the mechanics the same sort of thing started to happen.. the abs, traction control, and park brake lights came on so i immediately pulled into a parts store and got the alternator tested. both the battery and alternator passed and were deemed good. this confuses me because i assumed that this meant the beginning of the newly put in alternator being bad. any advice on what this could be?