This has happened at least a dozen times since I purchased the Model S in June 2019. In the last month it has happened 5 times and I believe that not only are both screen black, but, at least with the latest blackout, the headlights, turn signals, taillights, and hazard warning lights don't work (along with other functions). The Tesla service center looked at the problem again on July 8 and advised me: "Known characteristic. Future Solution." My service advisor told me that the problem is not unique to me and that their engineers are working on the problem. He acknowledged that it seemed like a serious safety concern, especially if it happens at night. I reported the situation to the NHTSA. I'm personally very concerned about driving the car after dark.