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I can hot see your van or what it is doing. All I have to go on is what you tell me. Going by what you have stated above. It sounds like you have a bad window motor or a broken regulator cable. The first thing to check is for power and ground on the brown and Dark/blue wires at the switch. Below is a wiring diagram.
I checked the power to the driver's window switch, there is none. I used a jumper wire and everyting works okay.
Where can I check for problems along the yellow wire?
Check for power trough the breaker. If you have power through the breaker. The most likely cause of the problem is a broken wire, where the wires run from the door to the pillar. Open door, look where the door hinges to the pillar, there should be a boot with the wires in it. The door opening and closing, bends these wires back and forth. This can cause the wires to break. But first make sure the power is going through the breaker.