OK, I located the connector going to the motor and applied 12 volts to get the window down, and when I reversed polarity, the window went up. Neither the key-switch nor the dash switch currently does anything.

What I'm seeing inside the tailgate are two switches.

One is the outside key operated. Turn the key to the left and it engages the switch; turn it to the right and, well, it doesn't turn to the right and from what I can see, wouldn't do anything if it did. The keys are tricky -- I have to wiggle them to get them to move at all in the ignition, and forget about the doors. So, the question is, when I turn it to the left, does it raise the window, lower the window, or move it to the opposite state (down if up, up if down)? Is it supposed to turn to the right at all?

The other switch is on the latch. As best I can determine, that switch cannot be engaged unless the window is down. When the window is down, it engages the mechanical safety, which allows the tailgate to be unlatched and allows this switch to be engaged -- if the window isn't down, that switch isn't going to do anything, it's not even going to be touched, it's blocked off by the mechanical safety. So, what is this switch for? It seems to be part of the motor circuit, but I don't see any purpose in it.

What fuse or fuses operate the rear window circuit?

 

So, I figured out the switch on the door-latch: it's bad.

Disconnected the wiring where it enters the body and found a badly corroded pin -- I assume it's s'posed to be "hot at all times". It's not -- it's not hot at all, currently. The other two pins are aged, but otherwise clean.

After I jumped the latch-switch, I got some response from the key switch. On the connector exiting the tailgate, Pin 1 is corroded and on top, Pin 2 is bottom left, and Pin 3 is bottom right. With no key in the switch, Pin 1-Pin 2 is open, Pin 1-Pin 3 is short, Pin 2-Pin 3 is open. With the key turned to the left, Pin 1-Pin 2 is short, Pin 1-Pin 3 is open, Pin 2-Pin 3 is open. I already know the motor is good. Therefore, I assume everything inside the tailgate, with the exception of the latch-switch (an interlock?), is good.

Now, if I can just figure out where the wiring in the body terminates. The dash switch? Fuse box?

 

wow...you got that going on!

There is a recent post thread that has the diagram if you haven't found it.

You should continue to document everything your doing and spell it out when you find the fix...this site needs a good set of instructions on troubleshooting the real window...maybe even some pics???

great job!

 

Yes please, I need some help with mine also. So any instructions would be appreciated.....

 

The switch inside the driver side latch is the safety switch it prevents the window from operating unless the tailgate is fully latched. If the bushings on your strike bolt are worn or missing you might have to lean into the tailgate to get the window to work, or if the switch is bad you will have to replace it before you can check anything else.