I have ready many posts on here about heater controls. Thanks to all of you for some of the pics and guides. Based on all of the information here I had the courage and know how to start troubleshooting vent control problems on my 2002 Blazer LS.

My Issue. I couldn't get air to move anywhere other than out the front vents, right in the face. So I proceeded to take the dash apart and take a look right behind the controller for the vents. I figured it was as good a place to start as any. I could not believe what I saw. The idiot before me had cut all the vacuum lines, ALL OF THEM, and "repaired" it with black electrical tape! So I found the first problem I needed to fix. I ran to the auto parts store to look for something I could use to patch the vacuum lines. I found something called Windshield Washer & Vacuum tubing, with an inside diameter the looked like it would work perfect. Attached is a pic of the back side of the vent selector switch with my repair versus his "repair".

 

The repair I did behind the controls did not fix the problem however. Following the lines back behind the glove box I found where all those vacuum lines go. Picture is attached. I tested out my repair with a little vacuum pump tester. I would not attempt trying to troubleshoot these vacuum controls without one. Had it for many years and never regretted buying it.

Right above and behind this connector is a vacuum actuator? I think that is what it is called. I figured I might as well test it. I don't know what it controls. It did not work. I took it out and moved the lever it was attached to. It didnt seem to make a difference where the air went. I tested the gray line it was attached too and could not get any vacuum on it. I followed the gray line back and it connects to a yellow line that went over to the drivers side.

After taking more stuff out of the way from the under dash on the drivers side, and taking out the center console to do it, I found that the yellow line had been cut here as well. Before fixing that I attached my vacuum pump to it and tested the actuator it was attached to, it worked! yay! So I repaired that.

Then I noticed another actuator that I tested, it works fine but the lever is not attached to anything and I notice a piece of duct tape covering a hole in the air box.

I assume that arm in the pic is supposed to be attached to something, probably the one that controls floor and Defrost directions. So now I am a bit stuck. Where do I get these parts? Well, not so much where, but what are they called? I need the actuator behind the glove box that's on the left had side. And whatever it is inside the air box that the actuator on the drivers side is supposed to be attached to. Thanks in advance for any help.