All windows go down; driver's window won't go up. Checked Motor-OK up and down at the motor. Bypassed switch, and same issue...down works but not up. Black wire from switch to door showed "open", yet with only two wires, I don't understand why the window would go down but not up. An open circuit should keep the window from working at all... The switch appears to only swap the polarity of the circuit. What am I missing?

 

Possibly a bad or weak ground?

 

Dunno. Exactly. My wiring diagram for a 2001 SL1 shows the drivers side window switch as being in essence two parts or switches. One is the up switch the other is the down switch. Most probably shown that way as it is all part of the window button pushed. One way being up the other way being down.
Dunno, I do not have a 2001 but I do have a wiring diagram for one.
So there for if you want to make the window go up, push the switch for it one way and the Brown wire will have power on it applied to the motor with the return being the dark blue wire and the window goes down. Push the switch the other way and the Dark blue wire will now have power on it and the window will go up and the brown wire becomes a ground. A black wire is shown as the chassis or body Ground wire going eventually to the negative side of the battery.
So if you are checking for continuity of the wire from one end to the other and you are assuming that the black wire (according to my diagram anyway) goes to the motor some how it does not. It goes to a left body ground splice pack located under the seat and that is connected to the body. This can not be bad if the other windows work and the one window still goes a direction, that is down.
Again while not owning a 2001 I can not predict the reliability of the window motor(s) but on my 94 it is not very reliable and the motors are problem prone. And will fail with the symptom being reduced operation, slowness and ultimately no movement. And generally in the up direction.
Rock auto carries motors for the car windows, the local Chevy agency advertizes through road side signs they will service Saturns and that is where I buy parts I can not get anywhere else The difference is on my 94 to replace the motor through GM parts, you buy the whole motor and lift assembly at about 2 C notes. Or the motor from Rock auto only for under $30.00 or so.

 

Uncljohn:
Thanks. I rechecked the circuit and switch. The lock button of the switch had broken and a piece of plastic was keeping the up from WO king. Disassembled switch, cleaned and repaired. Food to go. Now to fix the A/C for the desert summer.

 

Gotta have the A/C running. It generally is the first thing to be fixed! Moving here from elsewhere where A/C was nice maybe, not a requirement it did not take too long to actually have to learn how they should work so they can be fixed. R134 conversions work a whole lot better than they are given credit for..