Like so many here I have the problem where the passenger side is blowing cold air, & me the driver gets warm air. Since Ive read so many times about how to fix it, I went to the parts store & got myself an acutator for $105 & went to work. Well terns out that is not the problem, but let me explain & show some pictures that may help other not waste money, & maby someone can give me an idea of where to go next to keep looking for the problem.


heres a picture of the old and the new just in case this is infact your problem, & you need a new one. here are the part numbers.
the old one is the one right.



this is the area where you will be working, it is under the stearing wheel. you have to lay on your back in the floor looking up at the underside of the dash with your feet sticking out of the car.



but when you are looking up, everything will be upside-down. so Ill flip the pictures to make it easier.



there are two acutators on this side. #1 controls the hot air going to the drivers side & #2 controls the air between the front vents & the foor vents.



here is the picture of where they are located when you are looking at them on the car. #1 is pretty visible & #2 is bejind the back plastic box.



the easiest way to work on the acutators is to get the box out of the way by removing one screw (marked by the arrow), & then the box will come out the way the other arrow indicates it.



there are only two screws holding the acutator, & then just pull it hard, it will come straigt out. afther you remove it the best way to check the a/c is by turning the car on, then the a/c. & turn this white knob with one hand while holding the other to the vents & see what happens.



In my case, all it did is change the air from warm to hot. so the problems is somewhere before in the ducts.
does someone here have a picture of the air passages, & how the air gets routed, & where the doors are?

Im guessing that I have a door halve way open that is mixing warm air with the cold air, because I notice that the colder that the passanger side gets, the cloder that the drivers side gets. so there is some cold air getting mixed in there.

Ok, so that is all I got. now let me hear what you guys think. where to go from here?

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2001 Blue SLE - 1995 Black SSE - 1988 Black GTA

For the dual controls, there is just an air mix actuator for each side that controls that side's temperature. There is nothing that does that before those controls. The others control things like whether the air is recirculated, and where to direct the air.

Did you check the charge on the A/C system? One of the symptoms of a low charge is that the passenger gets colder air than the driver.

Good write-up on how to remove the actuator.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

it never ocured to me that it could be a low charge, because I just had the compresor change, the sistem flushed, & new charge aded. About a month after that, this started happening, & when I took it back the mechanic told me that he needed to start taking the dash apart to check the actuators. & when I read here about the easy fix I desired to do it myself. I guess I'll go to a difrent guy on Monday & check the charge just in case.

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2001 Blue SLE - 1995 Black SSE - 1988 Black GTA

This seems to be a very common issues with these 2000+ H-bodies, and I'd like to get to the bottom of it. Sometimes passenger side, usually driver's side. It's usually said, "buy an actuator," but I've never heard of a case where that fixed the problem. It must be something deeper than that; I agree, probably a broken door or hinge or armature somewhere inside the assembly.

(Wife's 2004 LeSabre has exact same issue. Recharge didn't fix it. I too bought an actuator, before I discovered that the actuator wasn't the real problem.)



I got better than a diagram, I have an entire 2001 (or 2002?) airbox/duct/armature system I bought from harofreak. I'll take some pics / videos when I get the chance, and add them to this thread.

Someday--hopefully before summer --I'm gonna tear out the 2004's dash to find the problem, and I'll get some pics of that, too.

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2004 Buick Lesabre Limited, Gran Touring
Bone Stock

1998 Buick Lesabre Limited, Gran Touring
Retired

The problem is more that we don't hear back on whether or not it fixed the problem. AFAIK, this is the first case that we'll have to investigate further.

Using this diagram, air is pulled in from outside at the base of the windshield, then routed through the filter (if there is one) and then to the blower. Alternately, depending on the setting of the inlet actuator, the air from inside the car is pulled in and recirculated instead of pulling in air from outside.


The blower sends air through the evaporator to cool and dehumidify it, and then depending on the setting of the air mix actuator, the air is routed through, around, or a little both the heater core. It happens in a similar manner for the driver's side. The mode actuator in this diagram shows the mode actuator that directs where the air goes....defrost, vent, floor.


If the actuators are good, and the system is charged, then it would be time to check the degree of movement of the actuators. If the driver's actuator does not move the same amount as the passenger, then the reason will need to be discovered. If it does, then checking through the duct work to see if something may be partially blocking the evaporator. Or there is a problem on the door itself.

If the actuator does not move fully, then pull the actuator and move the door manually. Does it appear to move fully each way, or does it bind? If it binds, then more work will be needed to find that cause. If not, then the problem could be in the sensors for the system.

Each side has an outlet temperature sensor in the duct work in the hush panel.


If this sensor reads improperly, it could affect what the system sees and then adjust things improperly. The one on the passenger side may be similar, so as a test they could be swapped if the are the same.

Edit - If you have access to a scanner, you could use that to read what each temperature sensor is seeing.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

I have an 01 Bonne SE and don't have dual air. However, my problem is the same. Two years ago at about 70K had in to dealer and they disassembled entire dash and $750.00 later didn't find definitive problem. They cleaned everything along the way and it cools better on driver's side but the difference between passenger and driver's side is still proportionally the same whether heating or cooling. Coolant level def. not low. Frustrated but pretty much given up.

Looks like I'm a little late to the party, but I truly and sincerely appreciate all the descriptions and pictures. I am diving into the ducts to try to diagnose/fix mine. I have cold air on the passenger dash and rear seat, but hot air on the drivers side and passenger floor. The air seems to come out in the right places, and when I switch from dash to floor, a few seconds of cold air come out the passenger floor before it switches to hot. My brain has been overheating trying to guess how the air flows through the system. I'll post something about what I find.

With yours being an SE, you likely do not have the dual controls. So, all of the mixing is done with one actuator - the one that would be for the passenger side on the dual control system.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.

Well a couple weeks agoI twisted my body up and got the drivers air mix actuator off. I do in fact have dual climate control in this car; maybe it's not common in an SE . I have always been extremely flexible, and was a ballet dancer when I was much younger. I can catch a ball or Frisbee at shoe lace level in a dead sprint without breaking stride, but making my body into a shape to reach the screws was ...challenging. Not to dissuade anyone from trying, but be prepared for a difficult reach.

Fortunately, I was able to do it outside on a comfortably warm day. Mine was held in with 2 5.5 mm screws. As Alex suggested, I was able to move the damper by hand and change the airflow from hot to cold, Which eliminated the ducts being the problem.

I checked voltage is at the plug. There were five pins with varying voltages across them, but I could not determine whether the voltages were a problem. It did seem that having voltage differentials across all combinations of pins confirmed the connectivity of the wires. The pins were numbered five, six, eight, nine, 10. I believe five was the power and six was the ground. The others are presumably signal related.
I decided to try the air mix actuator first. The new air mix actuator worked. The only problem was that in putting it on to the car I dropped one of the screws and it vanished. After about half an hour of looking for it I decided that mine would only have one screw holding it on.




5/8/17 @ 2:20PM

Glad that you got it working, and thanks for reporting back. If you can't find a screw that will work, you may want to check with Andrew (harofreak00) owner of Bonneville's Unlimited who could likely hook you up with one.

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*Gone, but not forgotten* - Black 2000 SSEi, HIR Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, 180 degree thermostat, HS 1.9 rockers, LSx yellow springs, Intense FWI, PCM, shift kit, push rods, and 3.4 Pulley. ZZP Power Log.