Car is stored in the winter, and I only run recommended tire pressures during roadster season. I'm having a crazy thought now that perhaps a grounding issue was somehow involved, although I admit that makes no sense.

I installed a new hard ground wire per a post on the forum at the same time I did the brakes. I noticed the lights on my MB leather shift **** are now also working again - they had been intermittently working (flashing) like a bad connection somewhere, but its all good now.

The horse may still be twitching, but I'm just going to end by being grateful that they are (apparently) working well enough to get them cloned. I never liked having the TPMS light on, and no way was I going to bypass it.