My Model S was built in May 2015 and was probably one of the last ones that shipped with 3G instead of LTE cellular service... I am finding that I am having trouble connecting to the car about 80% of the time -- particularly around my home and I suspect the problem is AT&Ts very poor HSPA service (3G but marketed as 4G on most smartphones by AT&T usually) which I know form experience on my iPhone is only suitable for basic texting. what's more... the streaming audio won't play a song for the 1st 15 minutes or so that I am driving my car. I haven't really noticed this too much in the past year b/c I generally listen to audio books from my phone, but once in a while when I have passengers in the car its embarrassing to have to try to reset everything so that music will play... the music often comes on when I am parking my car at my destination... then later when I am ready to leave said destination the last song will replay (I assume b/c it was already downloaded from before) but then I will have several minutes of dead air until the 3G service "wakes up" and plays another song. forget changing the station.. dead air. My car goes in for 36,000 miles service next monday and I am having them check the 3G stuff but I inquired about the upgrade and was told it's $500. I figured at some point during my ownership that Tesla would start charging for cellular service and if I had to pay for an extra service I might as well bring my own.. but my car often has trouble connecting both to my iPhone for tethering and random hotspots around my neighborhood. ever since Tesla changed things so that the car would not connect to wifi while in motion, I have had a really hard time getting wifi to tether.. so I don't know that bringing my own cellular service will be viable -- especially since Tesla said they will be charging "roughly $100" for this service any stand-alone data service for the car that I will find will most likely be more expensive that "$100 per year" so there is that to think about. but I don't want to pay Tesla this money if the 3G service is the culprit if it is unusable.. if they ever do start charging us, that is. still I don't know if $500 is worth it. I told service I would wait on the upgrade this time around so they can check everything but i'm kind of leaning towards biting the bullet b/c not having the connectivity is frustrating. That said, I am still getting software updates even over 3G.. so I know some things are working correctly.. as an aside, I even feel like I can "force" an update by connection to wifi and hanging out in the car listening to music for 5 or 10 minutes.. connecting to wifi and leaving the car immediately won't do it b/c the car will go to sleep soon after you exit... but if you hang out a bit it will may start downloading something and even complete the download while you are in the car if WiFi is fast enough. and then it will prompt you to update next time you go to the car... what should I do?