ok i just bought this van and the battery or amp light was on i figured ok its more than likely the altenator but i replaced it and it still isnt off and the sytem doesnt charge and it will die out when its jumped . iam still its something other then the battery or is it possible that battery could cause this? cuase once it is jump started even if the battery was bad it should still stay running but it doesnt.i checked all the fuse in the engine bay and all checked good. can anyone help with this situation? thanks for your time