...is all I am qualified (and just barely) to address.

If the motor works but the window gets stuck, you should next notice if the window seems to cock to one side or the other as it tries to start down. This is a sign that either the lubricant has hardened at some point, causing that side of the window to hang up, or one of the pivot points has failed due to a screw or rivet that has dropped out.

You might try "guiding" the window, gently, with a hand, as it tries to go down. Wiggle it up and down, back and forth, taking the weight of the glass off of the mechanism with your hand(s). If you can get the window to go down a little more, stop and get it back into the closed position (you don't want it to jam "open"). That will confirm a mechanism problem.

On the other hand, there could also be a limit switch that is not operating properly (I don't know how M-B designed its window regulators). An improperly operating limit switch could think that the window was fully open and stop the motor.

Which reminds me, when the window stops moving, can you hear/feel the motor still trying? That will separate electrical from mechanical problems.

Jeremy in Santa Rosa, California

__________________

"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
2005 E320 CDI . . 113,000 miles My car
Santa Rosa population 176,762 (2022)
Total. . . . . . . . . . . . 627,762
"Oh lord won't you buy me a Mercedes Benz."
-- Janis Joplin, October 1, 1970