Hello I'm Neal and I am here to help resolve your issue. If I cannot help I will opt out and refer your question to another expert.
It should just be a short or a bad compnent like the alternator. The dealer will be better equipped to locate the problem. If you really want to avoid the dealer, an auto electric shop can handle that possibly. You could be looking at anything between $200 and $500 in most cases, depending on what the actual problem is.