Any mechanics in the braintrust? I got a 03 F150 that the fan for the A/C and Heater will run with the key out of the ignition if I leave the A/C switch in any position other than off. It just started happening and it drained my battery. I've got it on charge now so I can take it in to get it checked. Any ideas what is causing the problem and approximate cost to repair? Is this something I can repair/replace myself?