It can be a broken wire in the hinge area, a bad switch, or simply a bad window regulator.
See this post for instructions on how to diagnose the problem:
Yes
In order to replace the drivers side mirror on a Buick Rendezvous, you will need to remove the door panel. You will have to disconnect the electrical connector and you will be able to remove the mirror and place the new one on.
Buick Rendezvous was created in 2001.
Take your door panel off and replace them...
No; 2007 was the last model year for Buick Rendezvous.
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0.......there is no 2009 Buick Rendezvous....2007 was the last year they were made.
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yes