The topic of how to perform the actuator recalibration procedure on Chevrolet , GMC and Cadillac Trucks and SUVs has become an ever increasing topic of discussion.
For manual systems it does not matter where the a/c controls are set but if you feel the need to do something, turn the blower switch on (I prefer speed 3) and set the temperature sliders about .5″ to .75″ from full cold.
For auto systems, press the auto button, with the key on.
Turn the ignition off.
Remove the HVAC/ECAS , 10 amp fuse in the underhood fuse box* or disconnect the battery for one minute.
*Fuse locations can vary from year to year and between different models. Hopefully I will be able to build a list for this.
Install the HVAC fuse or reconnect the battery.
Start the engine. On systems with auto a/c controls the controls will default to 74 degrees F when the ignition is turned back on.
DO NOT TOUCH the a/c controls.
Let the engine run for 1-2 minutes.
Turn the ignition off for at least 10 seconds but no more than 30 seconds.
Restart the engine and then test the a/c controls.
Hey Sparky!
Thank you very much for this information. My husband’s 2015 Silverado 1500 would only push out HOT air on the passenger side…MY side! It was horrible even during a Michigan winter. I found this site and told my husband we should give this procedure a try. He agreed, and it worked!! I no longer dread riding in that truck. Thanks again!
Lisa.
Hello Sparky,
I have a 2009 Chevy Traverse, any good way to recalibrate my ac? It’s just blowing air and I have no actuator control.
This is GM’s procedure without a scan tool.
Important: Do not adjust any controls on the HVAC control module while the HVAC control module is self-calibrating. If interrupted, improper HVAC performance will result.
Alternate Method (w/o Scan Tool)
Clear all DTCs.
Place the ignition switch to the OFF position.
Install the HVAC actuator.
Connect all previously disconnected components.
Remove the HVAC/ECAS fuse for a minimum of 10 seconds.
Install the HVAC/ECAS fuse.
Start the vehicle.
Wait 40 seconds for the HVAC control module to self-calibrate.
Verify that no DTCs have set as current DTCs.
Hi Sparky I have a 2010 Traverse with no digital temp controls, just a hot through cold knob from red to blue. The old blend actuator stopped working so I replaced and the actuator is now moving the blend door but not all the way. Upon actuator removal I can see that the blend door does not go all the way closed on cold making it blow a bit of warm air. Hot works fine but cold air demand does not go all the way. To verify a/c is working well, I removed actuator and manually moved door all way to cold and a/c is very cold!
After reinstalling actuator I tried the above method for recalibration but it didn’t help. Any ideas? By the way your responses and answers are fantastic and truly appreciated by everyone, Thanks!
Begin with the ignition Off.
Remove the HVAC 15 amp fuse for at least 10 seconds. The fuse is located in the interior fuse box.
Install the HVAC Fuse.
Start the engine and immediately put your hands in your pockets.
Wait at least 40 seconds for the HVAC control module to self calibrate. I recommend 50 -80 seconds.
Turn the ignition off for at least 10 seconds but no more than thirty seconds. Restart the engine and check HVAC operation.
If no problems were encountered by the HVAC module during this process the recalibration is complete.
Tried this on my 2005 GMC Sierra 1500 SLE w/manual controls. I could hear a click under the hood during the 1 minute the fuse was removed. Started it up, let it run for 2 minutes, it cycled through all settings & temp, turned it off for 15 seconds & restarted engine. Still the same, vent selection doesn’t work. I did this 4 or 5 times with the same results. The other 3 actuators seem to work fine. Am I one of the unlucky ones that has to spend money to get this repaired? Thanks
Sparky,
I have a 2015 Silverado that the ac is not blowing cold. It will blow hot but when you put it on cold it still blows warm. It will change through the settings from dash, feet and defrost. The only issue I have is it not blowing cold. The ac compressor kicks on as should and doesn’t short cycle. I was told that freon wasn’t the issue but the blend door might be jacked up. Can you tell me how to reset the blend door for my truck? Thanks in advance.
Alternate Method (without Scan Tool)
Note: Do not operate any HVAC controls while the HVAC control module is calibrating as this may interrupt the process. If interrupted, improper HVAC performance will result.
Ignition OFF/ Vehicle OFF.
Remove the HVAC control module fuses (F26DL & F34DL in interior fuse box) for a minimum of 10 s.
Install the HVAC control module fuse (F26DL & F34DL in interior fuse box).
Start the vehicle.
Wait at least 40 s for the HVAC control module to self-calibrate.
Turn the ignition off for at least 10 seconds but no more than thirty seconds.
Start the engine and check HVAC operation.
Thanks for the reply but it did not fix my issue. Any other ideas?
First confirm the refrigerant system is working correctly. Just because the compressor turns on it does not mean the system is working. A basic test is to find the two lines that go through the firewall and check to see if they both feel cold and are equal in temperature after the compressor has been on for several minutes. If they are not cold or equally cold concentrate on the refrigerant system. If they are access the lower temperature door actuator and see if it turns the door shaft when you command it to.
Turns out it was low on Freon. Thanks Sparky.
Hello Sparky,
I have a 2002 Cadillac Escalade with Auto controls. The AC/Heat Control Unit is not digital (No Screen with numbers) just knobs and buttons. Do you know if this recalibration process would work on my Escalade? And if so, which fuse do I need to remove and where is it located. I looked under the hood and the only HVAC fuses I see are a 25A HVAC Front and 25A HVAC Rear.
Any help would be greatly appreciated.
As you probably already know your vehicle does not have the HVAC/ECAS fuse. You will need to remove the radio fuse in the underhood fuse box to begin the recalibration procedure. Then just follow the standard routine as outlined in this article. https://sparkys-answers.com/2011/08/hvac-actuator-recalibration-procedure.html