[relative4]

2007 335xi sedan auto, 155K miles. The rear left window is responding erratically. Sometimes it works, sometimes it doesn't. When you operate the switch, sometimes nothing happens, sometimes it works perfectly, and sometimes if it's at the bottom it'll go up like a millimeter as if the pinch protection activated. The behavior is the same if using the front door switch or the rear door switch. I have run through the calibration, and when the window operates, the automatic one-touch operates perfectly.

The motor and regulator sound great, and operation, when it operates, is smooth. FWIW, I did replace the regulator 3 years ago. I was pretty sure it was a quality part, but I can't find now what brand it was. The problem just started this week.

There are no codes in the FRM. With a scanner, the only data streams I can see are the switch positions and the hall sensor. The switch positions always reflect accurately, for both the front and rear switches. So the switches and the wiring to the switches are good. The hall sensor state switches between high and low with no pattern that I can discern, but that seems to be true of all the other windows as well. Strangely, when I operate the front right window, the rear right window's hall sensor state follows the front's. I'm not sure what those sensors do, let alone what their state is supposed to look like.

Ideas? Thanks!