Chevrolet Repair: Inoperative automatic windows rollup, jumper wire, chevy van

Question
I have a chevy van with an automatic windows rollup operation, now WILL NOT roll up or down at either the driver's nor passenger's side. I attempted a troubleshooting using drawings from another Chevy wiring diagram and it sort of pinpointed the problem to a defective master switch (driver's side) - had the supplying voltages (12 vdc or more) on the main wire from fuse box or power source, and very little voltages on other wires (runs to switches connections) when the door window switches are being pressed either up or down. Note: Both windows locks are operating fine.

I hope I'm making any sense explaining my problem...hope to hear from you and provide some advice to remedy my frustrated problem.  I didn't want to buy and replace parts due to high cost and time wasting.

Until then,

"tj"

Answer
hi tj.  You may want to check the ground.  Most of the time they get their ground from the frame which can rust over time.  Try running a jumper wire to a good ground from the body of the motor and see if that works.  Good luck on it, and if I can help you in any other way, please do not hesistate to ask.

david