^^^^yep what he said about checking power with a multi-meter to see if any voltage is present. Then if not, you can trace the wire back to the connections, fuse box, etc. You do have a multi-meter don't you. Handy for these kinds of problems. It's rare a LED burns out, but a possibility. Having a good service and electrical manual is suggested too. Good luck!
2015 Electra Glide Ultra Classic
Mysterious Red Sunglo/Blackened Cayenne Sunglo
Stage 4 Kit
Vance & Hines True Duals
RC Component mufflers