I have found this weird problem with my E39. It started with buying an auction car that wouldn't run well enough to move on it's own power. After I got the engine running well and the codes all gone, I had some work to do on the rear alignment. Once that was all good I put the car back on the ground and the thing wouldn't start. No crank, No start. Ran the codes and came up with DME-EWS Interface. I thought my EWS may have went bad or the ring antenna. Replaced the ring antenna and tried to start with no luck. So, I removed the EWS and decided to see if I could see a burned or damaged circuit board. I thought to try it again with the board outside of the box and the car started right up. Put it all back together and tossed it up to a bad connection. It started many times after that. Shut it off long enough to change the oil, and once again no crank. Now it's down to every time I let the car cool down I have to unplug and plug the EWS in to get it to crank. All that being said it is also throwing a code for thermostat sensor problems. The engine is not getting too hot, the sensor is just bad and I have a new one coming. Has anyone ever ran into this with a EWS acting this way? I checked the connection and cleaned it with electrical cleaner and used dielectric grease, no change.