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.
Hi Allen,
Yes, I can. Could you tell me more about the issues that you are having?
Sparky,
I have a 2005 suburban 8.1 2500 with hvac problems. Blend doors need replacing. I am in SC also, can you diagnose and repair my truck?
Allen
Possible wrong part number installed?
I have a 2000 GMC Yukon with front and rear heat. I have heat in the back, but blows cold up front. I did replace the battery this summer. I checked the blend door actuator and it wasn’t moving. I replaced the actuator and followed the reset procedure numerous times using both methods. I can see the actuator moving through the full range, but when it’s done the calibration…it doesn’t move, but a hair. Sometimes, it doesn’t move at all after the calibration. Any thoughts?
I have been plagued with blend door actuator issues on my 2005 Silverado since it had about 5000 miles on it. Under warranty, the blend door actuator was replaced twice and the A/C control head was replaced twice. I’ve put another 2 actuators in, with continued troubles. Since I live in Texas, I just go through the reset procedure and unplug the actuator on the passenger floorboard until Winter. I love everything else about this truck.
This week, winter arrived and I reconnected the actuator. Tonight, I ran across your site, and in the comments section found your mention of the junction block on the passenger side of the dash. I walked outside, connected and disconnected each connector several times and BAM, it works like it should’ve been working for the last 7 years. You are THE MAN!!!! Thank you so much for your hard work on this site.