Auto Glass: faulty glass of the tailgate Jeep GW, grand wagoneer, switch fuses

Question
Hi Ben,I'm Fabio from Italy,I have a "little" problem with the tailgate of my '88 Grand Wagoneer,the glass don't open/closed with the switch of the dashboard and also with the rear lock.
The safety switch,fuses and cables are ok,the motor works good,...do you have any great idea about this problem?What could I to inspect?
Sincerely grateful for your answer,I greet you cordially.

BYE

Answer
Hello Fabio,

In the eleven years I have been fixing power windows I have only worked on one tailgate window of a Grand Wagoneer.  That was several years ago so I don't have a very good idea of what kind of problems are typical.  If the switch on the dash is working properly and the motor and regulator work when you apply power directly to the motor, I think your problem has to be a broken wire somewhere between the switch and the tailgate.  Sorry I can't be of much help on this one.

Ben .... the power window guy