Mystery electrical thing?

[Dravec]

It's the Onstar module. I've got the same module behind the glovebox in my 2000 Denali

Onstar?? Not that I doubt you, but where would the rest of the system be? I don't have an Onstar button or anything. Not like it would work now anyways, even if I did.
But still, I never would have guessed this old girl had that. I did have what looked like a car phone cradle that I pulled out a few weeks ago that was a "Genuine GM Accessory" according to the sticker on it. Would that have been related?

 

[AK49BWL]

That module of yours is not for OnStar.. If you had that, you'd have a small antenna on the right rear window, and the comms module would be under the right rear seat (and only appeared in the SUVs). Jury's still out on what you have in there.

 

[PlayingWithTBI]

Hell, disconnect the thing and see what happens or doesn't happen

 

[Dravec]

Hell, disconnect the thing and see what happens or doesn't happen

Yeah.... Me and electronics dont get along too well. I think I'll leave it alone for now.

 

[F4U-1A]

Go for a long drive, all bells and whistles on. Then put your hand on the heat sink, or use a temp gun. See if it is functioning. If it is cold, may mean the component it supplies is deactivated. But Alas still does not answer your Query.

 

[Wh4t3v3rs]

Maybe trace that wire bundle coming out of it and see if it leads to something or if it combines with more OEM wires...... Deductive reasoning will tell you OEM or not, and if its not, those wires will lead you to what it controls.....

If OEM, pull PN# off label and give a GM dealership a call.....