Originally Posted by TuckGraham
1. No they do not light up, just the sound.
2. Yes, no problems.
3. Nope checked that first.
And the clicking is very fast, like the light is out, but i replaced them and they are fine.
Sounds pretty strange. Its like the flasher relay is being told to flash and is sensing a bad bulb at the same time.
You could try replacing the flasher relay and see where that gets you.
Just out of curiosity, what year is your truck and do you have daytime running lights that use the same bulbs as the front turn signals?
Oh. I just saw you have a 1999 and bed lights. Did you happen to splice the bed lights into the trailer wiring by any chance?