HiCustomer can you give me a little history on the problem. Are you able to scan the vehicle for fault codes?
Ok, with the locked shifter it's possible that you have a faulty brake light switch. I've attached instructions on releasing the shift lever. See if that works for you while I look at some other information on your problem.
it took alot but i was finally able to get the transmission to shift using your instructions, thank you, also ive done some research on forums and alot of people with these symptoms end up needing the brake lamp switch, the only thing keeping me from thinking that thats the problem is that when i hit the brake pedal the brake lamps do come on
If there is a dealer nearby that's where you should get it. I would not purchase an aftermarket switch. You can probably purchase a new Genuine Mercedes switch online like this one here if you want to wait for it to be shipped. And you'll pay more. The part # XXXXX XXXXX 545 64 09. MSRP is $17.00.
For some reason I'm having trouble finding the actual procedure but I've attached the instructions for removing the underdash panel and also instruction for removing the pedals. DON'T REMOVE THE PEDALS! The article is just to illustrate where the brake light switch installs. The far right picture clearly shows the hole in the bracket where the switch installs. If you look at the picture of the switch I sent earlier you'll see a little locking tab. Press the tab and rotate the switch in order to release it. Then install your new switch by pushing down on the brake pedal and installing the switch into the opening and then rotating it into place. When you release the brake pedal it will "set" the switch travel.
Remove Underdash Panel
Illustration of Pedal Assembly
You're most welcome. Let me know how you make out. I won't be around from Saturday afternoon until Sunday afternoon but leave me a message and I'll reply when I return. Good Luck!