I have already had the plug and resistor thing done to my truck after I lost a few speeds on the dial, and all has been well for the past 2 years. Yesterday, after running back from upstate NY (about 4 hours) with the ac on I stopped home for an hour, took a 35 minute ride with AC on, stopped for 15 minutes. Got in the truck started it, drove out the lot and flipped the fan switch to #1, ac came on, drove 40 feet ,heard a pop and the fan went up to max speed, ac light was blinking, turning the speed dial did nothing, hitting the ac switch did nothing, turning the speed dial to off did nothing ! 15 seconds later it was back to normal, all fan speeds work,ac works fine. What gives??? Failure imminent? Any thoughts?