Ok, here's a new one. Driving down the highway for about an hour, turn on TACC. Speed is normal highway-ish, like 65 or 70. Then I shut it off, futz with the radio (don't ask), and go to turn it back on again. Nothing happens. The stick is dead for on/off, but the rotation still works to set the following distance. (Meaning no error like "Can't use that", "call tesla service", "feed me a sacrifice", etc, no response at all.) Luckily had a supercharger station a bit up the road, pull in, start charging, and reset both panels from steering wheel. Get some free electricity (Thanks Tesla!) while I use the facilities, and go back to the highway. Driving out onto the feeder road, stick still dead... does not actuate anything (~30 MPH). Get on the ramp, put the motors to work generating an ungodly amount of acceleration (Thanks Tesla!), merge onto highway.... and poof! TACC works again. Don't yet have the intestinal fortitude to reset both panels while driving at highway speed... and car was otherwise fine (radio, nav, energy graph all worked normally) so no threat to safety... just confused how the signal could be ignored...?