You may be correct, however replacing the solenoid plate in the transmission is not an fun thing. I think you are limited in the info the scan tool is giving you. The tool seems to be a generic OBD II and thus it will not show transmission codes, SRS or A/C codes. To be more certain where/what the problem is I recommend you get the car scanned with a scan tool that can reach into the Mercedes transmission codes. Your best way to do that is either buy a tool yourself (you can get them for under $200), or take the car to an independent repair shop that specializes in European/Mercedes cars. DO NOT GO TO A DEALERSHIP! The scan tool should come up with something like a 2221 or 2333 code either set or in storage. If you take it to a shop be certain to get the exact code number, not just an explanation as to what the mechanic interprets it to be. GET THE NUMBER and his/her opinion. Good Luck