Just purchased a 2000 Lesabre Limited yesterday, pick it up thursday.
On the inside of the windshield beside the review mirror there is a black box stuck on the windshield. The wires go up into the headliner with the wires from the mirror.
Any ideas what this box is?
The car has moisture activated wipers, auto dim rear view mirror with compass, auto dim outside mirrors along with alot of other options.
Just currious about the black box.
Thanks

OnStar most likely. Do you have any buttons on the mirror?

Would have to look when we pick it up on Thursday. Test drove many cars and kind of forget what had what lol.
Mirror does not have the red or blue onstar buttons.

Thanks.

Is it a big box? Maybe its some kind of remote start?

Not OnStar then if it doesn't have the buttons. Might control the auto-dimming of the mirror.

Pretty sure that is the rain sensor for the wipers. Our Ultra had that, and we saw what looked like optics on the windshield side.

Rain sensor for the wipers.

The auto dim is on the side that faces driver a lil sensor.

There'* also a small sensor on the back of the mirror, but not in a box or anything.