Hi guys, been awhile. Old Mrs Klankenborg is still around, just had a new exhaust and center driveshaft support bearing installed so she's back on the road as a DD. Mopping up a few old issues today. Driver's window has intermittently failed to go down. It always goes back up if it'll go down, but now it's not budging at all. The glass is not sticking as far as I know being that it was working up until last week.

I have replaced/swapped the window switch several times. Previously that has fixed the problem, until it comes back. What I noticed today (because it was dusk) is that there's some arcing/spark inside a known-good switch with no motor action. Never saw that before. The other three windows work, and the fuse has never blown. Without disassembling the door and replacing the motor, is there a way to check first if the motor is no good?