Posting this here, even though Model X, since it’s really not X specific. Just after loading 2018.20, this happened. Tesla doesn’t think it’s firmware dependent..... I have two load-sharing HPWCs, and a backup 14-50 (see sig). On the first drive after loading 2018.20, and returning home, plugged in the car and got: Ready to Charge, check Wall Power. Never had a problem, of course, in eight months. Car usually and has always charged to 80, down to 77, and up. (Once in a while, a rogue firmware had it go higher, but a reboot fixed that, or it happened when the servers were down; none of that is relevant here.) So, I tried the other HPWC, and the UMC using the 14-50. Reset the HPWCs with the button. Cycled the 100 Amp breaker is the subpanel and the main panel, nothing. Rebooted the MCU, of course (almost didn’t add that, it was so obvious that we do that for everything!) Called Tesla, and got a remarkably speedy answer for a holiday weekend when California is awake. Wonder if they are beefing up support? After she checked the logs, and some discussion, all she could say is that I should try charging somewhere else to show the house power is fine. Nearest Supercharger isn’t that close (guess I could go to the new Fredericksburg one!) or even see if the ev-go Chademo in Reston is open to test. But my real question here is, wouldn’t the HPWCs show ‘bad power’? If it was so bad that the car couldn’t accept it? And/or the UMC? She is putting in a mobile ticket to have a Ranger stop by to check the charge port. So, woohoo, looks like NoVa is in Ranger territory for some things (or they will call me, say, so sorry, come to Tysons! ) And actually she just called back to check that the UMC didn’t do any special light blinking when it was plugged in, and we did it again, and it’s one steady green light, as it should be (which makes me think the power is indeed fine). Where is the ‘power checking hardware’? With the chargeport, so that indeed could be the issue?