Well, I had to get the car towed home yesterday. Symptoms: gradual decrease in power until the motor was no longer spinning. Fortunately, I was in the right-hand lane of the freeway and was able to pull off on an offramp.
Lessons learned:
1) Check the batteries of your test equipment on a regular basis. My portable voltmeter’s battery was dead.
2) Keep your towing service – you never know when your car is gonna stop working. AAA was excellent and only took 15 minutes to arrive.
I REALLY hope the controller isn’t dead, as I didn’t want to buy a different controller just yet. At least I’ve got a lead on a (hopefully) more reliable one. Nothing solid yet.