1- check the fuses
2- will the window go down anymore?
3- turn the key on and go to that door and try the window button on the door
4- It could be the central window switch on the center console.
Remove the offending switch and open it up. Often they collect a lot of dirt and @#%.
It is best, if the switch needs to be cleaned, to do it over a towel to keep the tiny little ball bearings from rolling away. Spray some WD40 in it.
5- Do you hear the motor trying to run when you depress a switch? If so your window regulator needs repair.
Keep us posted?
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)