Take your door panel off and replace them...
The way that replace a window regulator in a 2003 Buick LeSabre front drive side is by removing the door panel. Next, disconnect the electrical connector on the regulator and replace.
Yes
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To replace the window regulator on a 1990 Buick Reatta, start by removing the door panel to access the regulator. Disconnect the wiring harness and remove any screws or bolts securing the regulator to the door. Carefully take out the old regulator, then install the new one by reversing the removal process, ensuring all connections are secure. Finally, reattach the door panel and test the window operation.
Most likely it is the regulator, either the cable is broken or the plastic at the top broke and the cable became unspooled and wrapped around itself. The window is held in by two screws that tighten a clamp on the window that holds pretty tight so it is doubtful it is that.
See this post for instructions and photoshttp://www.ricksfreeautorepairadvice.com/repair-topics/window-power-repair/replace-a-power-window-regulator
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