Funny you should post this. I had the exact same thing Happened to me just yesterday. I parked my car in the Tampa airport. I parked at 64% but forgot and left Sentry on. So when I checked it on Sunday, I noticed it had dropped 20% in four days, which is expected with Sentry on. So I turned it off. When I went back to check on the drain a few hours later, I cannot pull it up. Concerned I was still having the 5% loss, which would put me negative by the time I retrieve the vehicle, I was concerned the vehicle would drain to zero and sit there which terrible for the battery. So I had my wife drive in and check on it. The car opened right away with her phone app and when she got in it, it had only lost a single percent in one day since sentry was turned off but it did say connection lost. I can’t say for sure what the connection was stable for four days, and then for suddenly lost, but that was my experience.
Oh, by the way. I did contact Tesla support and they tried, but could not get it to activate either. They could tell me when it last connected and the battery state at that point, but their “activate” tools obviously could not work any differently than the app since the connection was down. 28.3.1.
