I got the replacement relay for the heater switch, dropped it in and it works just like it's supposed to. So here's how it works. The Car must be on for the heater fan to work. The heater fan must be on in order for there to be power delivered to the switch on the dashboard that turns on the heater. If the cars not on, no power to the switch. If the fans not on, no power to the switch. So there should be no way for the heater to be on unless the car is running and the fan is on. I'm trusting that means no exciting fires in my dashboard.
I got a bench power supply the other day. "What's that" you say? I'll explain. If you build any sort of electronic devices, you need some way of providing power to them to test them or operate them or whatever you have planned. Well a bench power supply lets you set the precise voltage and current (amps) you want to deliver to the equipment. "But Tim, you're not bright enough to build any high end circuitry" you say. Well, you're correct. But the great thing about these is that they can function as battery chargers.
You say "Well then, why don't you just buy a battery charger you dimwit?" Whoa, that was kind of harsh. The thing about these batteries that I'm allegedly getting someday is that they are 3.3 volts apiece. Not exactly your standard charger voltage. If one of them needs to be charged by itself for some reason, say it lags behind the others in the pack during a normal charge, then I can catch it up with this. I don't expect that to happen much because I plan to follow a fairly conservative approach to charging. But you never know.
Anyway, with that, I was also able to charge the 12 volt battery I'd installed a few weeks ago and have been running down ever since. With it nice and charged up, I felt it was safe to try that energy hog of a power steering pump. I'm pleased to say that the whole system worked flawlessly. I turned the wheels and the pump comes on right away. It stays on for 10 seconds after the wheels are straight again. If during that 10 seconds I turn the wheel again, the timer restarts. Plus no leaks! I'm very happy about that.
I also started modifying some of the carpet that lined the trunk, so that I can put it back in place. I have to cut out holes to accommodate the new equipment, but so far so good.
And you guessed it, still no word on the batteries.