Rear defrost won't workon cavalier

The Cavalier suffers from the infamous Purple wire problem. when you have this problem, the light comes on and timer works but there is no power at the rear elements. Cause is in the connector on driver's side, behind the carpet near hood release. Pull this carpet down and locate the Purple wire going into a green plug...press center of plug to open. Likely the contact is blackened inside, that is cause of the problem. You have two choices...clean the contacts and put plug together and defogger will work, for a while. I took the Purple wire out of the plug and soldered it to the black wire on the other side of the plug...make sure you get the right two wires. Look at the plug. The plug causes a high resistance contact and no voltage gets to rear. To prove it, disconnect one terminal at the window and measure 12Volts, connect the wire and the voltage disappears. Basic Ohm's Law. The plug contact is getting all the voltage. Don't let anyone tell you that you need a new switch, if the light/timer work. That won't fix it.

Take a test light to see if u have power,,,