How does this even work? [Archive] - Bimmerfest - BMW Forums

: How does this even work?

05-21-2008, 06:53 AM
i left my iX's lights on and the battery went flat.

went to jump it straight from the battery and i noticed something REALLY strange. the ground was a red cable but it was marked with a (-). and ofcourse the black one was labelled with a (+). makes sense so far BUT.... whoever replaced the battery put the battery in BACKWARDS! the positive terminal on the battery was on the negative to the car and vice versa.

eh??????????? how? everything ran fine before. now that i jumped the car, i blew the ABS relay which is going to be replaced this week but how does a car run with reverse polarity on the battery being hooked up?