1998 Ml320 Key Remote
 

I Just Recieved My New Key Remote From The Dealership Thats Replacing A Damaged One However It Is Not Unlocking My Door With The Buttons ( Key Does Open Them ) How Do I Program It? Also My Engine Battery Died And Now The Factory Bose Stereo Is Asking For A Code Where Do I Get A Code? I MISSING THE OWNER MANUAL.

Remote
 

That information should be in your manual that came with the car.

Rev. Dr. G. Church of the Sub-Genius

the key needs to be programmed by the dealer, or an independant repair facility that has the star diagnosis system, that is a diagnostic computer that connects to the car, the remote unlock cannot be enabled any other way.

Some times the replacement key will operate the central locking system by synchronizing it to the receiver.

Key in ignition & turn on & then back off.
Hold key in hand, depress & hold lock button.
Press unlock button 5 times (quickly).
Release lock button & depress either lock OR unlock 1 time
That procedure must be done in less than 10 seconds from the time you first insert the key into the ignition switch!

But many times the key will need to be authorized with a scanner