Sigh - my wife was driving the Model S to LA (from SF Bay Area). Made it to Harris Ranch. Plugged in to supercharger and it didn't charge. First time every plugging in to a supercharger. Called Tesla and after 3 hours+ of remote diagnostics and trying several chargers they determined it was a physical problem. The car was able to accept a regular charge, just not a super charge. Needless to say she had enough range to get to Hertz and Tesla came an picked up the car and towed it back to Fremont. Note to self: Try supercharging before you really need it!