When I took my Lexus out this morning, the window controls on the driver's door didn't work. The controls on the other doors were still good, and the window lock and door lock control both still worked on the driver's door, but the actual window control didn't work.
I measured the voltage of the power coming into the driver's window control switch, and it only measured around 1.5V. I measured the voltage in the other doors, and they all measured 12V. The power splits between the driver's door and the other doors and then goes right into connector BN1 for the driver's door.
I opened up the kick panel to measure the voltage at BN1, Terminal 1, and found some crusties
I cut back a little of the bundle sheathing and tugged on the wire, only for it to break immediately
It seems as though when the sunroof drain was clogged over the years, the channel that the drain runs through would back up with water, and these connectors are in that channel as well. Luckily, it looks like this was the only terminal and wire that was affected. I replaced the terminal and the corroded portion of the wire, and now everything works properly again.
Cheers