Power windows

If you have a passenger window that has an inoperative function, regardless from which switch(es), the cause can be either switch including the one that works properly. Most commonly that is the master switch, then the door wiring, because those get used most often, but the next suspect is the passenger's switch. The reason is each switch actually has four sets of switch contacts in it. Two are used when that switch is activated, and two are used when it is released. Those two sets of contacts in the passenger switch are part of the circuit when the master switch is activated.

As a test, replace the passenger switch first, or swap it with the rear window switch. If that doesn't solve the problem, we'll need to perform some voltage tests.

That's exactly what I said. The released switch, (passenger switch) has two sets of contacts being used when the master switch is activated. In total, there are four switches in the passenger side circuit, (two built into the master switch and two built into the passenger switch). All four are used anytime either switch is pressed either way.

To say that a different way, when one function does not work from the driver's switch, there is a 50 percent chance the problem is caused by the other switch.