You would either need to check that power and ground is coming out of the switch to the motors, or check it at the motors. Switches were known to fail on these years. Does the left rear work with it's dedicated switch?
You could apply power and ground to the motor, and it should go one way or the other depending on the polarity. The chance that you had two motors fail at the same time would be unlikely, so they would probably work. That would lead you back to having to do electrical checks of the circuits. If you have a test light and can use it, you can check first if power is getting to the motors, and if not trace it back in the circuits. I got you a schematic for reference.
Here are some guides and diagrams to help you start testing
Check out the diagrams (Below)
Please let us know what you find.
Saturday, August 13th, 2011 AT 2:50 AM