
My wife looked up "T/M system malfunction" and found a thread here that said it might be due to a low 12 V battery. Sure enough, putting my voltmeter on the little battery showed it at 7.6 V.
I shut off the car, connected a 6 A 12 V car battery charger to the battery without disconnecting it from the LEAF (started drawing the full 6 A) and went to work in the usually-neglected ICE car. On our return after 8 hours, the charger was down to near zero charge current. I pulled it off and tried to start the LEAF, hoping to make a test-drive around the block, but no luck. The T/M display was gone but the display looked like this:

The voltage on the little battery with the LEAF shut off is now 12.47 V
Any suggestions other than "tow it to the dealer?"