My 2012 E550 Convertible has some interesting electrical quirks. The Cruse control and the brake "HOLD" function just quite on a fairly regular basis, but they come back. This happens about 50% of the time. Last Thursday (7-11-19) I got in the car after running into the bank, started it and the power steering did not work. I called a wrecker, a friend to pick me up and then tried it again and it had no power steering. I went back into the bank to wait in the AC and when my friend arrived to pick me up (after 15 min. or so) I decided to try it again.............and of course the power steering worked fine and has worked fine ever since. Any advice on what this could be? Also any electrical experts In the Mid-Continent ( Kansas City to the Dallas Fort Worth Area. I am in Okla. City area, but the OKC Dealer has seemed a little technically inept in the service department.