Ta-Dah! Fuse #23. Thank you so much - she moved that red cover to the POS post after the miscue. There are other markings of course, which I've told her about.

Regarding blind spots - thx for the advice. For interstate driving in particular, I do move the mirrors on everything I drive outward a little past the point I cannot see the side of the car. And sometimes a little more. That's saved my car's paint many times.