I have an 03 5.7L 1500 that I'm having trouble with the trailer lights. The truck is fairly new to me but looks like a factory installed wiring system. The problem is with the left turn signal, it will not indicate breaking or turning? The wiring to the truck does though. I have a 7 pin and a 4 pin and both do not work. (all other pins work) I have checked the fuse and it is fine, the one thing that I noticed was that when removing the fuse the clicking sound ( relay?) stops and when replaced it is noticeably quieter than the right signal clicking? (If that makes sense?)
Any info would be greatly appreciated.