Buick Repair Questions? Ask a Mechanic for Answers ASAP
Hello and good evening. The window regulator is most likely the issue. Replacing it is not terrible. I will upload the instructions for you. Once you remove the door panel, you can follow the directions. Just as you proceed, secure the window so it can't slide down. Just let me know if you need any other help as you work through this job.
Your JA Expert,
Front Side Door Window Regulator Replacement Removal Procedure
Notice: Refer to Fastener Notice in Service Precautions.
Important: Start the vehicle in order to ensure maximum power to the window motor. This is required to fully seat the window for adjustment.
Tighten the window clamp fasteners to 11 N.m (95 lb in).
If it is broken, you should be able to lower the window enough to unbolt it from the regulator. If you need more freedom, use a pair of cutting pliers and try to cut the remaining cables and you'll be able to move the window up and down at will. Below you will find the pictures larger. I resaved them zoomed.
Once you get the new one and get access to the old one, it will be relatively obvious what you'll need to do.