Mercedes Benz CLK window not shutting

possible your window reg has become loose allowing it to drop after it has closed, whatever the problem your door card will need to come off to find the fault

try taking the window right to the bottom then holding the switch for a further 3 to 5 seconds then bring it up and try that

Just to confirm " wiggy4170 " solution

Synchronizing power windows:

If the power supply was interrupted (battery
disconnected or low), the windows cannot be opened or
closed by the Express feature. To resynchronize the express feature, press side of power window switch to resistance point until the window is completely closed and hold for additional 2 seconds. Repeat procedure for each window. The automatic full opening and closing procedure of the windows should now be restored.

Another slight variation from Mercedes ,


Engine running all doors closed, send the window to the top and press full, second click then hold for 30 secs, then send the window to the bottom and do the same on the bottom. You may need to repeat this a couple of times and then all should be fine.

When I use try to close the driver's window fully it will then open itself about 6cm after I let go of the switch.

None of the suggestions above seem to work, if I hold the window button to close the window as suggested ... the window opens itself about 1cm after aprox. 20 seconds even though I am still holding the switch in the close position!

Any suggestions?