Heater and A/C actuators?

topo4u2 · April 19, 2003

Hi all,

Not sure if my post pics will work but here goes. I bought my 1995 GMC with these actuators disconnected. I got these pics from a friends truck. Anyone had this problem? Im missing the springs and white nylon spacers. My ac does not work either. Please let me know?

thankshttp://www.picturetrail.com/topo4u2

carguru · April 20, 2003

Those look like part of the linkages for the actuator. The white nylon pieces probably attach to another link or to part of the door. I believe that the springs are to dampen the movement when the doors hit hardstops. The doors will not work without the nylon pieces or the springs. The nylon pieces probably broke off and the springs popped out. Either that or the person who owned the truck before gave up trying to figure out what was wrong. What is the problem with the A/C? Does that particular actuator work? There should be at least a couple more actuators on that plenum. Do those work?

topo4u2 · April 21, 2003

Hi Carguru,

Thanks for the reply. Well lets see. The actuator does seem to work but like you can see all the doors do not work with the acutators disconnected. I have defrost and floor air. When I hit the ac button on dash the little light on switch does not light up and no cold air. The doors could be screwing up the cold air but the compressor is not kicking on either so that might be from low R134A. Those rods hook up to that electric motor in the pic and one end goes up high to the plenum that you see in pic. That one has come off on my truck and I cannot see how it hooks up. Almost looks like something is missing? I know this is really hard to diagnosis but I want to try and at least find the replacement rods either from dealer or wrecker and give it a try.

carguru · April 22, 2003

I'm pretty sure that that actuator pictured is the mode actuator. The linkages control 2 sets of doors. That actuator should be the one that controls the airflow to the dash panel/floor/defrost. You should be able to check this function by switching the fan on high and changing the modes. When you switch from hot to cold or vice versa, do you feel a temp change? You should be able to check the functions by switching the fan on high and adjust the temp knob. If not, that might be part of the problem. Does your compressor even cycle when you turn the a/c on? If the blend door is not working, the heat will be enough to overcome the effects of the a/c. The dealer should have microfiche of plenum assembly. The junkyard may be a good source for those parts, but if the parts did break due to aging of the plastic, the junkyard parts might not last very long. Good luck, happy hunting. Let us know what you find.

topo4u2 · April 22, 2003

Hi Carguru,

No the compressor does not cycle at all. Im thinkin it may be either the dash switch, wiring or low on freon. And yes if the doors are screwed up it could affect the air temp.but no the compressor is not coming on.

I do get temp change when I move knob from cold to hot, so thats working. Im having a bit of trouble with the air from ducts though. Always on floor or defrost and thats where my actuator is causing trouble for sure. I may go to dealer this week and see what he has. Im very concerned about where the linkage attaches to the top of plenum as I cannot see at all how it attaches. Oh well, need some luck on that one.

Wingnut · April 22, 2003

I was having the same problems as you are in my 92. Not going from defrost to floor and whatnot. But my AC compressor came on...So I don't have much insight there.

But...

I circled the spot on your pic where I had to re-attach one of the linkages that was hanging down...It slides right on/in....IF you have it, and IF you have it lined up just right, as there is a flat spot on in the hole to insure that it is aligned correctly. Kind of a PITA to get up under there, and twist it around, and compress the spring all the while trying to line it up correctly.

Not sure if this is your problem, or not. Just adding my .02.

Hope they helped.

topo4u2 · April 22, 2003

Hi Wingnut,

Thanks for the reply. I have not looked under there for a while but I will take a look at that spot. The one that actually concerns me more is on the other pic. Its the one all by itself at the higher spot on plenum. You can just barely see it? I wish I knew how to get the pic on this reply to show you? Thanks so much for answering..this problem has been aching me ever since I got the truck last year but I hope to solve it.

Wingnut · April 22, 2003

OK, I went out there this morning and looked at it again....It appears that I circled the wrong spot on that pic.

I took a pic, and circled the arm that had fallen off (I took it off again to point it out), and the spot where it needed to be re-attached.

But yours appear to be attached.....hmmmmm.

Oh yeah...To post an image, copy the url for the image. Then when typing your post, push the "image" button above the typing area. This will bring up a place for you to paste -or type- the pictures url. Press "OK", and the tags are automatically added in your post....I think that made sense.

topo4u2 · April 22, 2003

Hi Wingnut,

Thanks for the reply and pic. Actually the pics I sent are from another 95Gmc not mine. If I get a chance I will try and take one of my truck. I went to the dealer today and ordered another rod cause I need the 2 white nylon bushings and springs. But I still will have a problem cause if you look in my other pic(not the one you circled) you will see the top connection into the plenum that I think is screwed up. It has come right out and I believe that goes right inside to a door. Making any sense??? Im still having trouble putting a pic on here ..oh wellhttp://picturetrail.com/topo4u2

I also think your set up is a bit different.

topo4u2 · April 23, 2003

Hello all,

Well I went to the dealer today and bought that extra link(I only needed the spring and retainers) but oh well it was much easier to put in that way. Link cost $30.00.

Anyway 2 things. Im almost sure that something is broken inside the dash where that one top link hooks up because there is nothing inside that it attaches that i can see. Maybe the door is broken? Secondly there does not seem to be a lot of movement in that electrical box when I use the switch on dash. I may have to look into that as well. One thing, Im pretty much convinced that this is not why my compressor is not engaging. that is more likely low freon or a wiring problem. When I put power to clutch it cycles so its not the clutch.

Anyway if anyone has any ideas on that hookup on that top linkage please let me know..its on that pic at www.picturetrail.com/topo4u2.

topo4u2 · April 23, 2003

Hey wingnut.

If you could put that other pic of my linkage on this page it would help tons to show my dilema. I still cant seem to do that.

topo4u2 · April 23, 2003

Hi Again,

Ok, I put a pic on my site www.picturetrail.com/topo4u2 of the lever that Im talking about. The silver end!! That is the one that does not seem to have a connection at the plenum? Does anyone know how it connects?? I think something has broken off inside but I could be wrong? There is an empty hole where it goes in.

Any help would be really appreciated.

Wingnut · April 23, 2003

See if it works.

topo4u2 · April 23, 2003

Thats perfect. now I can show you what I mean. If you look at 11:00 oclock on the pic you will see a metal link(silver color) which is connected into the black duct. That is where mine has come out. I need to know how that re-attaches. Its a ##### to get at too. There is a hole where it used to go so I wonder if anyone has dealt with this before or not?Im not sure if a bolt came out or the duct has broken off? Looks nasty to get inside and look too.

Any Ideas??

topo4u2 · April 26, 2003

Anyone have any ideas on this one. I know likely not too many people have had this link apart. I just need to know how it hooks up to the duct inside. ??? ???