there are many things that wil happen when batteries are hooked up backwards... ALL BAD
It can burn out the computer as well as mptprs and wiring and much much more.
This is most likely not a job for you to try to fix yourself.
if you try to fix it yourself, you are likely to repace a bunch of stuff that may not need to be reolaced and not replace the things that do.
It electrical system will need to be completely checked out professionally.
Sorry for the bad nes, but you do not want to make a bad situation worse.
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