One problem related to underhood wiring has been reported for the 2007 Dodge Ram 3500. The most recently reported issues are listed below.
Power distribution box underneath fuse box melts down and smokes excessively. Problem comes without warning while driving. In a matter of 30 seconds the dash lights go out and motor dies, driver loses power steering and power brakes and is extremely hard to control, keeping in mind this is a heavy duty truck made for commercial work, in my case I use it for hauling implement equipment and various steel products. The March 15th incident was the third time this has happened. During the last time the windshield washer pump turned on and pumped fluid on the windshield making it virtually impossible to see. Problem was not diagnosed first two times to the shop, only a replacement part was installed. Problem occurs about every 12,000 miles.