rear passenger window on 2002 Cadillac Seville STS

my rear passenger window wont roll up it happened once before but a couple days later it rolled but now it wont go up and its been about two weeks any suggestions?

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1 answer
Windows fail due to the following:

-faulty motor
-faulty regulator
-faulty swtich
-faulty wiring
-chafed glass runs
-detached glass to regulator bracket

I suspect a motor issue probably brought on by very dry glass runs. Have the system checked for power and ground.