screen on my Mercedes is blank radio and CD work on the navg/radio command

Hello, Tap around the trim for the screen. If it changes anything on the screen, there is damage to the screen, screen signal wires, or the solder points that connect the screen to the signal wires. It is a normal LCD like an old iPhone or TV, and can be damaged pretty easily if contacted the right way. I once set one down gently, but there was a screw I didn't see. The result was a shattered screen. In fact, it was the same MFD2 unit that your car uses. Replacements are expensive, so try resetting by pulling the radio fuse for about 15 seconds first. You can install an aftermarket unit to save quite a bit.