My 99 cherokee has had some electrical issues before but it was never a real problem, but now I live in Seattle and I think all the rain is making it worse.

I had a ton of water coming in the driver's side door so it was basically always wet inside, and my gagues would go crazy or not work at all. Then the other day all the gagues stopped, my lights went dim, the radio turned off, and the whole jeep eventually just shut down. Now it won't keep a charge if I jump it.

So I think the alternator is dead, but before I replace it, how can I know what's wrong with the electrical system so that it doesn't just short out again?

 

First thing is to fix the charging system, low voltage will cause some pretty weird stuff to happen.