Last month (coincidentally on Friday Jul 13 ), our Model X (late 2017 production) suddenly stalled on the highway (freeway) while my wife was driving home from work. The accelerator pedal became unresponsive. Luckily, she was able to coast and stop the car on the shoulder, and no one was hurt. My wife called the Tesla roadside assistance for help. Multiple error messages appeared on our screen as follows: Air suspension needs service (Contact Tesla), Unable to drive (PULL OVER SAFELY), acceleration reduced (contact Tesla Service when convenient), Car needs service (Power reduced and car will not charge), Car needs service (PULL OVER SAFELY), Vehicle systems shutting down (contact Tesla Service). My wife couldn't shift the car to "Drive", even after rebooting the car. After about 15 minutes, the car died completely. Approximately 30 minutes later, the Tesla tow truck with flat bed arrived and the operator made a quick judgement to call for police assistance to stop behind our car for safety reason. The tow truck operator was also very knowledgable to boost the 12V battery to turn on the screen in order to shift into "tow mode". We got our car towed to the nearest SC. Since the SC was closed, we just dropped off the key and returned the following morning to get a our loaner which was a Model S. We finally got our car back yesterday (Aug 10). It turns out the problem was a faulty front electrical harness which got replaced (part no 2072447-60-A). The length of time was due to waiting for the parts to come (a few weeks), the time required (about 4 days worth of work) to install the front harness, and various tests they had to do to ensure all functionality is working as designed. I drove the car around yesterday, everything seems working and in order.