Display problem after changing battery

[resh77]

I didnt use my E36 325 1995 model for about 2 months and my battery went flat, but after I change the battery all my display stopped working, it didnt turn on. I faced the same problem sometime ago and I sent to service center, they charged my about RM300 to fix it, but I think it must be some minor problem. I really hope any 1 here can help me....