If one of the Mercedes-Benz C-class (W204) windows is not completely closed, you need to check if extraneous objects between the glass and the guide-for example, leaves. If nothing is found, you can try to adjust the glass actuator. To do this, you need to close all the doors, insert the key into the ignition switch, and turn it into position 1 or 2. Then, pull the button on the door control panel until the window closes. Hold the button one second after that. If the window reopens, repeat the procedure
