I have not been able to duplicate the symptom That symptom may not have been described correctly in the first place. I assumed that it was a chassis battery drain but it may have simply been the chassis battery voltage not getting where it needed to go. I left the RV sit for a week with the house battery disconnect engaged (i.e. house batteries off.) Per Hooligan, I found that my step controller was a drain on the chassis batteries and have that temporarily disconnected. The chassis batteries, two weeks later, are reading 12.73volts. Obviously, I don't have a battery voltage problem. I've started the engine a couple of times and it fires immediately - just like it always did before.
On Sunday, I plugged in the shore power and engaged the house batteries. Tonight, I tried to start it and, on the first try, got something close the the symptom at the campground. THe starter did not turn over and all I heard was a click. I went all the way off with the key, went to start, the started engaged immediately and the engine fired.
JWalker and I have corresponded on this several times and he believes that it might be my ignition switch. I agree that is one of the more likely culprits. I'm also concerned that the ignition solenoid is not fully passing voltage to all of the components attached to it when the switch is turned to on. In that case, the ignition switch itself would be OK but the solenoid transfer is incomplete. I know for a fact that happened on the battery disconnect solenoid because I was getting 12.5 volts into it and 9.6 volts out. I exercised the store/use switch a couple of times in succession and that problem has not reappeared.
The time for our big trip (4,200 miles) is coming and I was really hoping to have this problem resolved before then. I desperately want to prove something bad but am about out of ideas for how to go about that. I'll test everything again this Friday, having let things sit for another couple of days.
2000 Georgie Boy Landau 36' DP
2005 Saturn Vue toad