This past August the ladies and I took the bus up to Acadia in Maine for a week long vacation.  We stayed at the Bar Harbor KoA  and had a lovely site right at the water's edge.  While we were there we visited the Seal Cove Auto Museum on Mount Desert island.

Seal Cove specializes in automobiles from the "Brass Era," that is cars primarily made prior to 1916 and thus named due to the large number of brass lighting fixtures and other accessories. You can see why this might be a particular favorite museum of mine!

The day after I returned from SteamCon in Seattle I got into the car to go to the day job and discovered that my battery light was on in my 2007 Toyota Yaris.  Being an old Volkswagen man I resisted the urge to get out and hammer on the the alternator with a monkey wrench.  Instead I turned everything off and then listened carefully to the engine RPM as I turned on the rear window defroster.  When I pressed the defrost button the engines revs did indeed drop about 100 and the engine lugged for a moment until the ECU gave it a bit more gas to smooth out the idle.  Good. This exercise told me that the alternator was charging the battery and that the problem was with the warning light itself. I could safely drive the car for the rest of the week and figure things out at my leisure.

This morning I started working the problem . . .