Before I had an MCU1 -> MCU2 swap done I saw this message: Climate keeper not available due to system fault. After MCU1 -> MCU2 swap the message was still there. Tesla service had missed that during the MCU1 -> MCU2 upgrade visit (and HW3 upgrade at the same time). I had to take a trip to pick up a college graduate so I had to run without this fix. Tesla did diagnose the problem while I was driving (I was in touch with them about it) and by the time I got back they knew the fix - it was a faulty AC actuator. Replaced it and so far so good. Posting just FYI, seen reports of this being a pinched harness or a firmware issue. For me it was something different. Some pictures attached to show the problem.