Electric window stuck down, can I lift it up manually?

[JK973]

Well, I tried the switch from the other window, no luck there, then I applied 12v to the 2 pins, the window went down OK, but going up was very juddery and after about 2 seconds it stopped and then wouldn't move up or down, checked fuses, all OK, just seemed to die. So in the end I've undone the bolts on the mech arm and moved the window into position manually, then locked the mech arm back in place, so the window is up, but still not fixed unfortunately!!