After changing both cores I am in the process of putting my dash back together and came across a plug that I cant figure out where it goes. It comes from the harness that has the fan speed control wire and actuator control on the left of the dash. It is fastened to the topside of the dash sub-frame. Thanx..

https://www.dropbox.com/*/acs6xjx2qx...57.31.jpg?dl=0

https://www.dropbox.com/*/iqssbpdbh8...05547.jpg?dl=0

Sorry Thats on my 2002 Buick rendezvous

By "topside of the dash sub-frame" do you mean it'* near the top of the dash? If so check your daylight sensor (little black dome)

Hey thanx for looking yutzybrian, just noticed my pic links aren't working, hopefully this helps.
https://www.dropbox.com/*/iqssbpdbh8...05547.jpg?dl=0
https://www.dropbox.com/*/acs6xjx2qx...57.31.jpg?dl=0

And I have the two sensors in the center of the dash and the Alarm Red LED isolated..but good suggestion.

if you dont have the hud option could be for that

No its on the right, by the passengers Airbag unit. I do have the HUD unit which has like a 16 pin plug on the far left. I'll have breakfast, and if no answer by then I'll just do another tear down. I suspect it plugs into the HVAC assembly and the dash sub-frame is hiding it. Luckily I was only half way done. Will post my results. I guess now is a good time for a million pics to create a how-to. Didn't think of it when I started, I was certain someone had already done so. But after searching the net I couldn't find one.

Most people shy away from dash pull outs. Too many screws/nuts/bolts etc. Frankly, I don't like doing them either. Too much time on my back upside down.

I just take lots of pictures and put the screws/nuts into labeled bags

Couldn't agree more. I wont say its my least favorite task but defiantly not on my bucket list. I will admit the Rendezvous dash is more of a pain than I thought. Other GM'* iv done had the dash and sub-frame as one. So once you've got the dash out of the way the HVAC assembly is free and clear. The Rendezvous however requires a complete tear down to get to the HVAC assembly. The Dash is bolted to the sub-frame which looks more like a metal dash vs a tubular support frame. Then the HVAC assembly is bolted to the sub-frame. To get the sub-frame out the steering column has to be removed as its bolted to the sub-frame. Once i removed all the bolts i just didnt see the point of leaving it on the floor in the way. So just like peeling the layers of an onion with me crying all the while. All the cables line up and fasten within inches of its mate. So for the most part 99% of the cables are a no brainer. In all honesty I was to eager to get the damn thing back together and simply didn't pay as much attention as I should have. Thus the stray with no connection in sight. Well hoping to it, will post my results later this evening.

Well guys, cars all back together and I am embarrassed to say that plug belongs to the dash courtesy light.