I have a 14 RK and purchased a supposedly 14 streetglide rear fender. The guy kept the wire harness so I had to purchase one. I got it today, installed the rear fender and ALL lights work except the brake lights. I checked the two bullet bulbs and appear to be working fine. The flashers and turn signals work. Just not the brakes. Anyone run into this problem before? Do I need to get a flash at the dealer?
Since you changed from a 3 light setup to a two light setup - chances are the BCM doesn't know that and will need a flash. You might try running the 4 ways for a while and see if it learns the new configuration.