Power window Buick

[kaycee]

At witts end here on my 02 Buck Century, drivers side rear window wont roll down all other windows work . Wont roll down from master switch (front drivers side)works all other windows .Got new motor / regulator swapped it out same problem ,swapped door switch out to other side same thing no roll up on drivers rear. allso old and new motors swapped over and still wont work on drivers side. Have swapped relays around and have power all the way to motor WTH am I missing here