got to be a breaker tripping, and resetting itself. my buddy had a similar problem with his 04 tx chopper. I replaced his bulbs and it has been fine.

 

I have had some lighting issues as well. I think the headlight bulb was becoming disconnected (loose) from the wiring, but I am not sure. Neither high or dim worked. I would take it out to replace it and it would start working again.

Since then, I have burned out a couple of bulbs. When they dim burns out, I still have high beam to get me home at night.

 

The above issue was on a AI '05 LSC.

 

I replaced his bulbs and it has been fine.
start with the simple stuff.
cheap to try.