It sounds like your window regulator has let go. It is a mechanical device that is powered by an electrical motor. The electrical motor part is fine, just the mechancial part is not working as it should. This is almost always traced back to a plastic piece that has broken or cracked . . . either a plastic pulley or a plastic rail slide. You can get them aftermarket for around $80 but that doesn't include changing it out. My 5th one let go a couple of weeks ago. It's really a joke the way these things are made.

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2010 Lexus RX350 still new
2003 BMW X5 3.0i w/sport package w/68K miles. (gone Thank God!)
2002 Dodge Ram 2500 4X4 cummins diesel w/198K miles, custom repo truck
2009 Scion tC w/46K miles
2007 Suzuki SV650 custom streetfighter
2000 Lexus GS400 w/165K miles