Well, I just learned something about batteries. Thanks foglefar! The 16.4V is measured while it's charging. I took the measurement because I've seen batteries fail internally and voltage become reduced while charging. Kinda like a capacitor when the dielectric begins to fail. I just included that info so folks knew it wasn't failing like that.
I've got her on the charger now. At lunch I'll run over and see if she behaves differently with a charge on the battery. If so...time for a new battery. If not...I'll get the relay. Both the battery and the relay can be returned so I'm not too concerned about using a little trial and error to diagnose the problem.
