Desertbiker, welcome to the HDTimeline forum, while others will weigh in shortly take a bit of time to check out the Self Help tab for starting & troubleshooting, and the Search tab, just type in keywords on your subject and you will find related threads.
That said, RL has you covered, as to why, you list your location as San Diego, where coastal salt fog air can easily work it's way into electronics parts on a bike, and if you had some work done, it could be the previous servicer did not put dielectric grease in all the connectors exposed to air. So as you dissemble things inspect the connections, burnish them and coat the contacts to inhibit corrosion intrusion.