I had a strange problem with my Model 3 last weekend. I was going on a short trip and I loaded up the trunk. Then about 20 minutes later I got in the car and headed to the freeway. After 5 or 10 miles I engaged the cruise control, but I got an error that said (something like) "cruise is not available" I tried a few more times -- same error but no other error. Stopped for a snack and the car did not auto lock. I tried the phone app and locking had no effect and no error message. I got back in the car and tried to see what was wrong. Nothing was wrong that I could see. 10 minutes later I came back to the car and I get an error message that the trunk is not locked. It turns out that it was just half-way latched. It there was an error message about it, it was during the time I wasn't in the car. Closed the trunk. Everything works fine again. Silly rule for M3 owners: If your cruise control (or AP) doesn't work it might be the trunk isn't closed. What other conditions might cause a CC or AP failure???