1999 Mercedes Benz 430e

Electrical problem
1999 Mercedes Benz 430e V8

My car battery died and so I had it jump-started not sure if it was still good or not. I then noticed after starting my car that not everything was functioning. My keyless car remote wouldn't work and electronics in my car such a my seats, my driver/ pasenger side window would'nt roll down, and my signal lights would'nt work. And so after the charge not staying in the battery with 2 attempts, I had it replaced with a new battery. Thinking it may be because of a weak btery but now with a new battery th problems still remain. I believe my car was jump-started backward in with if this is the case, how would I fix this and what is the range of repair cost?
August 20, 2010.

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