ONCE AGAIN (went thru this SAME problem with the drivers side, rear window), I had rolled the electric window down and heard strange pop/grinding noise, apparently from the internal window mechanism. The window went all the way down (has the automatic operation feature) and then, after I somewhat recovered from the SHOCK of thinking that the same NIGHTMARE with the electric window was recurring, I activated the switch to begin closing the window. The window started slowly upward and then abruptly fell all the way down into the door. After working with the window for about 10 minutes, I was able to gently slide it up out of the door and hold it in place, in the fully closed position. While pushing it upward, I could hear a noise consistent with a cable coming loose, or something being off-track, etc. While holding the window in the fully closed position, I had my wife activate the electric window switch and could hear the mechanism operating to the closed position. At the end of the sequence, I felt something come up under the window, or up against the bottom of the window, which held it there. The window remains in the fully closed position, but cannot be operated at all. If you attempt to open the window even slightly, it will fall/slide into the door. OF COURSE, when we took this into the dealer for repair, we were told that we would be responsible for the costs, even though we were lucky enough to have the special CHAMPION CHEVROLET, 6 year/75,000 mile extended warranty. (What a JOKE..!!) So long story short, to this day, the window remains in it's fully closed position.