It happened on Wednesday the day before Thanksgiving. Let me preface by saying that the car is in my garage and plugged in. I hadn't driven it for about 3-4 days and the temperature outside was about 20 degrees. I was at another house away from the Tesla. I was trying to show my brother-in-law the Tesla app but it wouldn't connect. I thought it was an app issue. I shut it down and restarted but still no luck. I even uninstalled the app and reinstalled but still didn't work. At this point I was getting concerned that something was wrong with the car or something happened to the battery being so cold outside. Well I wasn't planning on going home but did later that evening to check on the car. Approached the car and the lights flashed and the door handles presented themselves. I sat in the car and nothing happened. The dashboard or the touchscreen didn't turn on. Pushed the brake and nothing. Obviously sometimes it takes time for the car to wake up when you push the brake but nothing happened after a couple of minutes. Next checked the charge port and was blue. I unplugged and plugged back in. I would make the noise like it was locking but then only turn blue. Not sure what the blue color means. I was getting very concerned at this point. Also mobile connector wasn't showing the green streaming lights like it was charging the car. So now I look through the owners manual to find out what the blue color charge port indicates but could not find it. Honestly I was skimming pretty fast and might have missed it. Not knowing what else I could do I called Tesla's toll free number. I explained the situation to him and he told me to go to the car and unplug it. After doing this I sat down in the car and amazingly the dashboard came on but not the touchscreen. Bottom of the dashboard it had the caution triangle and it said that the 12V battery was low and the car may shut down (the car didn't even turn on). At this point the Tesla representative took down my VIN. He asked me to push the toggle wheels to reset the touchscreen which worked and the touchscreen turned on. But the car still wouldn't start. It appears that he was checking on something and then asked me to start the car and it worked. The caution triangle disappeared and everything seemed to be okay. I asked him if this is a concern for the 12V battery and said no. He said that the battery was reading low but is back to normal. I drove the car the next couple of days and haven't had any problems. What does concern me is that after getting the car running that night the car was only charged to 220 and I know when I checked it a couple of days ago it was at 233. So during this time period when the car wasn't working it wasn't charging and loosing charge. Concerning in the fact that if I left a 50% charge and went on vacation for a couple of weeks this would have bricked the battery. Obviously this would be covered under the battery warranty but shouldn't have to go through this especially with car plugged in. Since the car is working fine for now I will discuss the situation at my annual service.