My 04 issue
Disclaimer: I don't know $hit about electronics, but I can tell you what happened with my 04.
When my EHC was going out, I had no lights on it when I hit run. At random times when it did start, the light on the EHC would come on Red and send power to the Ingnition Mod and that would light up the Red Led.
If you have lights on your EHC, and none on your Ig Mod, it would think Ig Mod. I actually think Shovelhead Cowboy has one for Sale in the swapmeet!
Similar thing happened to my buddies 03 Bulldog where the EHC was good but the Ig Mod was bad. Had enough power coming in from EHC but not enough going out.
Just my inexperienced 2 cents.
Good Luck