How do you program Mercedes Door opener 2004?

Take a look at the underside of your rear view mirror, you will see three small black soft buttons located on the left hand side. These are the "homelink buttons". Make sure that you are not sitting in the garage while you do this. Place your key in the ignition and turn the vehicle on. then press and hold the outer 2 of the three buttons, you will see a small orange light start to blink intermittantly on the far left underside of the mirror- when that light blinks very rapidly let go of the buttons. What you have just done is cleared any old information that may have been stored in the vehicles system. Next you want to take your garage door opener and hold it up next to those 3 little homelink buttons. press and hold the garage door opener button simultaneously with the black button that you would like to assign to that device- push and hold that until that little orange light flashes rapidly again.

Make sure that your garage door "rolling code" feature is turned off when you do this, or the system will not be able to link up. There should be a small switch on top of the garage door unit that will allow you access to this feature.