I recently purchased a 99 Jeep Wrangler. I have recently started having trouble with my lights. Most times when I turn them on , all is good. Then there are times that when I pull the switch on I might have dash lights and no head lights or tail lights or head lights on and no tail lights. I'm hoping that this would be a switch problem and not a wiring problem. If it is a wiring problem is this difficult and expensive?