I am also experiencing the one rear blinker not working. I am going to dive into it and will let you know what I find. So far all hazards work (front, side mirrors & rear). All brake lights (both rear and top middle on cab). All driver side blinkers good (front, mirror and rear). Front, mirror passenger blinkers work but not the rear. Yesterday I went to change the light bulb and it didn't fix the problem. I turned the hazard lights on and i got this "shorting/electric" sound as if something was about to catch fire. After turning hazard switch off and on the noise went away and hazards continue to work. Still no passenger blinker.