Dad has a 1995 F-150. The turn signals wouldn't work so he replaced the bulbs. they both worked.next day on the way to the cabin they went out again. on the way home they worked then went back out. so he replaced the flasher. they still don't work. the windshield wipers work cruise control doesn't work and 4-ways do not either. where should we start and what should we do. Dad's a diesel mechanic so he has some ideas but needs a second opinion. Thanks, Leidy