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A/C Recirculate door actuator or control head?

OK, OK OK! Replacing the actuator really did not lend itself to pictures and I really wasn't in a picture taking mood! In any event, here is what I did. The recurculate door actuator is located on the front of the evaporator/heater housing, just in front of the blower motor. Basically between the firewall and the evaporator housing. Its held on by two sheet metal screws and one plastic locating peg. One screw is pretty accessible and easy to remove, but there really is not enough room to see or get to the other screw.

I removed the steering column bolts and related brackets, which allowed me to lower the steering column down to the drivers seat. Then removed the three screws at the top of the dash and the two 13mm bolts on each side of the dash at the bottom. This allows the dash to rotate down so you can at least (almost) see the actuator and the second screw. With the dash out of the way and by laying on the passenger floor and contorting myself just so, I could get a ¼" socket (7/32 IIRC) and a small ratchet on the screw. I managed to remove it about 98% of the way. However, I spent over an hour trying to get the last little bit of the screw out. The problem is once you get your hand back there, you cannot see the screw, so its all by feel. And since the screw was almost out, it would move around and it was just impossible to get the last ½ turn required. I tried using long needle nose pliers, screwdrivers and anything else I could find. I was trying to get the screw out, but not break off the plastic mounting peg. As luck would have it, I broke off the mounting peg.

That might not have been the worst thing, as I was wondering how I would ever get the screw back in there once I replaced the actuator. After I got it out, it was literally hanging on by a thread, probably less than ½ turn and it came off. So I took the broken peg and screwed it onto the new actuator. After orienting it as close as I could, I mixed up some epoxy and applied it to the broken peg. I then placed the new actuator in place and installed the easy to reach screw. Just to make sure, I attached the wires and it move the door as it should. By then it was dark and I had to rotate the dash back up to close the doors (truck was outside). Came back the next afternoon and rechecked everything and the door moved correctly. So I guess its OK. I'm not too worried as there is not a lot of force on the door, so it would probably be OK even with the one screw holding it. The epoxy should hold the other mounting peg I would think.

I'm sure the book says to remove the evaporator housing, but that would require draining the cooling system & AC charge, so I wanted to avoid that. What is really aggravating is that I had the entire assembly out to replace the evaporator & heater cores a while back and could have done this in 5 minutes then. If I ever have to remove the housing, I will check the operation of each motor BEFORE I remove it so I can change them if necessary. Really I hope there never is a next time, as that is just a pig of a job.

After looking at this, with really no effort on GM's part, this could have been a 30 minute job or less. Why they design some of the stuff the way they do is beyond me. Its stuff like this that makes me think there is a good reason they went bankrupt.
 
Bobbie- i may have missed it, but was the recirc light on or off when you had this prob? I have a non-functioning recirc button... light does not come on button pushed on or off... and it comes on very randomly whenever it wants (when button pushed on) but even then no light on button.
 
Steve93mustanglx said:
Bobbie- i may have missed it, but was the recirc light on or off when you had this prob? I have a non-functioning recirc button... light does not come on button pushed on or off... and it comes on very randomly whenever it wants (when button pushed on) but even then no light on button.
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The light worked with the button. Its only connected to the switch, it has no idea if the door is actually moving. I would think your control unit is bad - that is fairly common. More expensive to buy but much easier to replace!
 
bobbiemartin said:
After looking at this, with really no effort on GM's part, this could have been a 30 minute job or less. Why they design some of the stuff the way they do is beyond me. Its stuff like this that makes me think there is a good reason they went bankrupt.
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Engineers do not have to repair the $hit they design. It has to go together on the assembly line quickly. Then it only has to last 3/36 and pay whatever for the 10% of failures. This is not an exclusive problem to GM.

The big electric drive mine haul trucks for example... In a show and tell meeting the engineer was showing the new wheel motor and planetary gear set design. The mechanic in attendance wanted to know how he was supposed to be able to fix the thing with the small access hole provided vs. the old design. Rare and then why redesign the part for a mechanic? Only if the operational cost goes through the roof maybe it will get redesigned...
 
Thanks for the description. I think these trucks have less maintenance jobs that are crappy than the other brands and they are more reliable than the other 90s trucks.

I have worked on ford trucks for friends before and now I just refuse, they royally suck to work on.
 
Now you know why I only do A/C work on Heavy trucks and Heavy equipment. I can pull the A/c heater box out of a Mack R model in 15 minutes. And I make more money too. And the best part is the guy driving that Mack in grueling off road dusty dirt or hauling 600 degree asphalt does not even ask what the repair will cost, JUST FIX IT !!
 
dangerousdave said:
Thanx, Bobbie; I have to do this now.
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Yeah, no kidding. Now my recirc door is messing up too, except mine is doing some WIERD crap like another failed control head. Mine will only fully close the door on fan position 1 or 2, on 3 it will half way close, and on hi it won't even budge. Once it's closed it will stay there though. Sometimes I can move the temp control back and forth and cycle the recirc button a few times and it will move the rest of the way. It's tight in there too, but GM says it's doable without pulling the evap out to get to it. I'm gonna try the relay repair on my control head first and see if that helps it before I dive in and change the recirc motor.
 
THEFERMANATOR said:
Yeah, no kidding. Now my recirc door is messing up too, except mine is doing some WIERD crap like another failed control head. Mine will only fully close the door on fan position 1 or 2, on 3 it will half way close, and on hi it won't even budge. Once it's closed it will stay there though. Sometimes I can move the temp control back and forth and cycle the recirc button a few times and it will move the rest of the way. It's tight in there too, but GM says it's doable without pulling the evap out to get to it. I'm gonna try the relay repair on my control head first and see if that helps it before I dive in and change the recirc motor.
Click to expand...

I'm certainly no expert here, but its my understanding that the motor works or it doesn't. I would look at the control head before you change the actuator. You can get to the wire for the actuator without too much trouble and make sure its getting the proper signal from the control head. Control heads are a little more expensive to buy, but much easier to change!
 
bobbiemartin said:
I'm certainly no expert here, but its my understanding that the motor works or it doesn't. I would look at the control head before you change the actuator. You can get to the wire for the actuator without too much trouble and make sure its getting the proper signal from the control head. Control heads are a little more expensive to buy, but much easier to change!
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Yep, this is my 4th control head since I've had the truck. It's been a year since the last one was changed, so I figure this one is due.
 
Steve93mustanglx said:
where do u buy your control heads from?
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I used to get good pricing from the local GM dealer, so I was buing em that way. I don't get my 20% over cost anymore, so I guess EBAY will be next. I'm about ready to see what it would take to swap in a 96-99 style as this one off 95 is pissing me off.
 
I just got mine 2 Saturdays ago from Rock auto for 160ish. It is not the same as the one I removed but works very well (long term I obviously need to wait and see). It was the same on the front but only half as deep as the original. I am guessing it is an updated part?
 
Well I dodged a bullett with the recirc door. I started to do the relay fix for the control head until I seen that it says that it won't work on a 95. So I dug into the dash wiring and started checking things. I had good voltage(within >1 V of actual) at the actuator, and had a solid ground going to it as well to trigger it. Yet it still wouldn't move with the fan on high. So I started chicking the ground which checked good at the actuator, but when I traced it back it turns out that some GM engineer had the bright idea to ground the entire HVAC box through the fan motor plug. I felt it and after only 2 minutes of running on high the plug was so hot you couldn't touch it. Turns out the ground pin had melted itself inot the plug and the plastic had made it's way in and was causing high resitance and a positive feedback into the ground wire for the HVAC. I cleaned up the male pins and replaced the female ones since I had some, and I added in another ground after the plug in the harness. Now all is well and it switches to inside almost instantly even on high now.

So it goes to show, don't assume the wiring is good just because it has proper continuity to it. Check for high resistance the old fashion way first. Now if I could get the mode door to move as quickly as the recirc door does now. And hopefully fixing the ground will also allow it to stay on full cold as the blend air door would begin to move to heat after about 30 minutes before.
 
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