He is in a different city and I wasn't there when things went haywire, so I don't know exactly what he did. He says that when he flipped the switch to the Run position everything lit up as usual including the odometer but within just a couple of seconds there was an audible click, like a relay popping, and everything shut off; the alarm did not sound. He disarmed with the key fob and got the usual double flash of the signal lights. However after that the next couple of tries got the same result as the first try, just a couple of seconds of dash lit up and then an audible click and nothing.
He then removed the battery, tossed it on the charger, cleaned both terminals and cable ends, pulled the fuses and made sure the prongs were not corroded, and even went so far as to remove the Power Commander. Put all back together and tried her again. This time the ignition stays on and he gets dash lights but there is no sound of the fuel pump starting up.
I found the link you posted and have sent that to him but probably won't hear from him until later today or tomorrow. I know nothing about the H-D security system and haven't been much help. I hope the link will allow him to reset; thanks for the response.