Help with Tailgate glass releasing
 

I have an 03 blazer xtreme and im having trouble with the rear tailgate glass popping open. The button on the dash wont release the glass but if you hold the button on the tailgate down you can manually pull the glass up but it wont pop the glass up. With the glass open and you push the button you can hear and see the accuator working but i cant figure out how it releases the catch to pop the glass open.