I drove my Model S up to the Grand Canyon from Phoenix on Tuesday. Wednesday morning when I got in the car and shifted into drive it threw up an error "Pull over Safely, Restart Car to Drive". Tried restarting the displays, turned off the car, left it for a while, nothing would fix it. AT&T claims to have cell phone coverage up where I was, but they didn't. So neither my phone, nor my car's connection would work. So when I borrowed a phone to call Tesla, they weren't able to connect to it remotely for diagnostics. So in the end, Tesla sent a couple guys up from Scottsdale to haul my car (and me) back. Turns out the drive unit is bad, so they're replacing that. For some reason, despite the car being under warranty (it's ~6 months old), having the service agreement, and having 24/7 roadside assistance, I was still charged a surprise $100 ranger fee when I got to the service center... which wouldn't even cover 1/4 the cost of the trip they made, so why bother? Anyway, apparently practically new drive-units failing is still a thing, and not just under heavy acceleration ... sometimes just while sitting in place over night.