Turn Signal Problem

My right turn signal started to flash rapidly when I turn it on. I checked the bulbs and replaced (even though they did not appear to be bad), still flashes rapidly. I had a trail wiring harness so I disconnected it, still does not work. There was a plug that attached the wires from the truck to the rear lights, which is where the trailer harness was attached, I removed it thinking that it might be the problem and it still does not work. I checked the bare wires from the truck with a tester and I can get the tail lights to work when I turn on my head lights and I can get the left turn signal to work but not the righ turn signal. I followed the wire conduit to the front of the truck and I did not see any areas that looked pinched or damaged. I then lose it when it gets to the front of the truck.