Hey everyone

Im having an issue with my 2000 buick lesabre A.C. system. Its blowing cold as ice on the passenger side, and warm on the driver side. The actuator behind the glove box works. Its filled with freon, idk what else to look at. Im at a loss. Can someone help? Its damn near 100 degrees here in utah.

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I don't know the system, but it would sound like a piece of ducting has fallen off or been blocked by ?. Have you done any under dash repairs lately? Try putting the a/c on full and crawl around feeling for cool air moving under the dash.
Your system sounds like the Automatic Dual Zone HVAC system, option code CJ2. It has separate temp control buttons for the passenger side in the RF door armrest.

There are 4 actuator motors in the HVAC system (actuators are not all the same). The left air mix actuator controls temperature on the driver's side and appears to not be working. Location of this actuator is shown on the attached shop manual page.

If you could take the car to an auto parts store that gives free trouble code scans, that may reveal more about what is happening. Better still would be borrowing or renting a scan tool for online troubleshooting. Attached is a typical code B0237 for defective left side actuator.

One check would be to remove the actuator and check for binding in the door. RockAuto.com has a budget line of actuators that are fairly inexpensive. It might just be worth buying a cheap one (SKP no SK604111 ~$20) to see if that is the fix. The GM part no is 89018375 or AC Delco 15-72972.

We can use the Buick Shop Manual to go a different direction if the problem is elsewhere.


The left side of the hvac housing, thats on the driver side correct? And do I have to pull the dssh to get to the actuators?

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Yes the left side is the driver's side. Usually there is a big reference arrow in the drawings that points to the front of the car. Here is a view of the right side of the HVAC module for reference (pg 1-134). It shows the actuator you could see through the glove box.

No, dash does not have to be pulled. Removal instructions for the driver side actuator are on pg 1-228 and 1-229. The left insulator panel has to be removed first (8-582 & 8-583). Then the knee bolster (8-583 & 8-584). And finally the Instrument Panel Module (8-493 & 8-494).


I am just bearly seeing this post. I had some stuff come up. But that is a lot of information. I really appreciate your help! I found another actuator that isn't working, it on the driver side, if you take off the knee bolster and the look up on the right you can see the actuator, would you happen to know what that one controls?

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Viewing the driver's side of the A/C housing, the actuator on the right (to the rear of the car) is the Mode Actuator. It controls where the air comes out. As the mode air door rotates, air comes from the defrost vents, dash center vents, or floor vents.
I finally got around to looking at it. And I know I need both actuators on the driver side. They part numbers were worn off. Would you happen to know them? Could the actuators be interchangeable?

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Just to back up a step on the troubleshooting, does air come out of the correct vents when operating the control panel buttons? (Defroster mode comes out of the windshield vents / A/C mode comes out of the dash vents / heat mode comes out of the floor vents) If so, the mode actuator is working.

The Mode Actuator is GM part no 89018376. Also known as ACDelco no 15-72645. RockAuto has it in their SKP economy line as SK604146. This one is not interchangeable with the other three actuators.

The Left Temperature Actuator is GM part no is 89018375 or AC Delco 15-72972. RockAuto has it in their SKP economy line no SK604111. Again this one is not interchangeable with the others.
I replaced the actuator that controls where the air comes out of. Floor, windshield and the mid. It works great now.
I replaced the temp control actuator and its just stuck on hot. The actuator won't move when I change the temp. I don't think the door is binding. I can move the door by hand easily. I also tried the actuator on the passenger side and the actuator works when I plugged it in on the passenger side.

Could there be bad temperature sensors?
Bad wiring?

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There are 6 temperature sensors and 2 light sensors in the HVAC system. See attached pages from the shop manual on the sensors.

A scan tool is the easiest way to check the system from here on. It can reset any old faults. It can also recalibrate the actuator motors. It can read the sensor temp values. Any faults in the HVAC that it can detect probably will not turn on the dash service light to alert the driver.

A few other ideas to look at:

Check to see that temp control buttons are not stuck. This includes the buttons on the HVAC panel and the steering wheel.

While in A/C mode, try setting the desired temp to a low number like 66 deg. But don't set it all the way down at 60.

In the heat mode check to see if the left temp actuator motor moves any while varying the temp setting.

There is an air intake hole on the front of the dash (see sketch) that draws in air for the inside temp sensor. The suction at this hole should hold a small 2" x 2" piece of paper in place. If not, the aspirator hose may have become disconnected or plugged up.

If not tried already, disconnect the battery for a few minutes and reconnect to see if the system resets.

The sensors can be tested individually with an ohmmeter to see if they are working. If the outside temp reads correctly on the control panel, that sensor is working.


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