I installed a new Alternator on my girl's car. I detached both battery cables.
However her friend reconnected the battery wrong. I heard a pop and changed it back. however now the radio,The power seats, Windshield wipers,
And sunroof, And door locks will not work any advice.Please help Bimmer
down in N.C

Connecting the battery backwards is a "bad thing" at the least there may be some blown fuses, but the odds are that one or more electronic modules have been damaged by the reverse polarity. A diagnostic scan of the car will probably help in figuring out what is no longer operating. Then it becomes a matter of replacing modules until everything works again. Note that some of the modules have to be coded to the car, which requires the services of a full-up diag system.

I installed a new Alternator on my girl's car. I detached both battery cables.
However her friend reconnected the battery wrong. I heard a pop and changed it back. however now the radio,The power seats, Windshield wipers,
And sunroof, And door locks will not work any advice.Please help Bimmer
down in N.C


you will probably find that you will be replacing your alternator again

Did you ever get a resolution. I have the same exact problem. However, everything works for a while after sitting overnight, then shuts down.

rodgers.crowell@us.army.mil

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