My rear defrost does not work on 2008 Chevrolet Impala

The switch light comes on, the fuse is good, I have voltage at the terminal on the right of the rear window and the left side is grounded,and I even read voltage across the defrost wires in the glass and at the ground terminal. ?????

Unhook wires and read resistance across the grid. I dont know the value but has to be enough to generate heat! Can't be 0 nor infinite and still work.