2012 GMS Terrain - I have no air coming from the front cabin vents,

Have you checked your controls to see if your vent system is on defrost, floor vent, floor/dash vents or just dash vents? Defrost only will divert all the air to the windshield. Floor will not sent any air to the dash vents or just a whisper of air. That is what you need to check first.

I have the same issue 2012 terrain no air coming out of vents replaced filter and even the blend door actuator still same issue-- air and ac blow fine from bottom but not out of vents checked all my fuses they ok has to be some actuator that controls redirects air to vents...HELP

On the dash there is a symbol of a person in a chair. There is an ^ and one that points down. If the actuator is not working, than perhaps this switch is inoperative. If you push the arrow a symbol will pop up on the center screen and who a person in a seat with the air flow direction being forced on to him/her. If the flow points only to the head, and no air comes out the top vents, than perhaps the actuator or circuit board running it is bad. If the windshield vent works and the flow to the floor works, but when the flow to the floor and top of the person does not cause flow from the dash OR just the ^ pointing to the top of the person does not send air from the dash, it could be the actuator or door flap not working or the circuit board malfunctioning.

tenspeed, another very good guru posted a schematic of the system. The actuaors are run by vacuum lines so you may have a hose lose or a hole in the air lines. That will stop the actuator doors from operating correctly. See if that may be an issue. Thanks tenspeed. Here's a basic HVAC flow diagram that might help.

Hello Califcarson, thank you for your post No matter what function I select the air just keeps coming from the floor the ac works fine because it freezes my feet when I select ac, so is my blend air because I can control the temp- but it just keeps coming from the floor- the vents them selves are manual control by passenger but just can get air to come out of vents or defrost- I download your schematic but its too small for me to read even when I zoom the pic the resolution is to low so I can not zoom it in to see... do you know what the control actuator is called and where its located? so one of two things is happening either the motor that flips the door from bottom to top is not working or it is not getting signal to flip I put my autolink AL619 to see if car has any error codes but it don't thanks again

On the schematic, I open word and slide it to the word page. I then can click on the picture and move it to open it further. See if that helps. If what tensed has shown, there are no electric motors, only phunatic actuators that control the movement of the doors. So there may be a hose lose, off or has a hole in it. I am not sure about taking apart the dash. I'd try an auto air conditioning shop for an estimate and diaganoise before removing screws and such.

Check your air filters because dirty filters can be one of the reason. Also check whether the vent properly. Or else call a technician for repair. http://www.airdexinc.com/about-airdex/service-area/

For sure check the cabin air filter. I just had the exact same problem. My filter was filthy, so i bought a new one for $11, changed it out, and everything is working great again. The filter should be located behind the passenger glove box. Instructions in the user manual are very easy to follow.

for those people who have a problem with the vents not working the problem is the module directly above the gas pedal it is malfunctioning and it is not hard to replace remove the two panels under the steering column and the metal plate you will see a computer by the gas pedal remove the two bolts which are 10 millimeter pull the computer down then remove plate computer was attached to 3 bolts pull plate down then remove module easy to do at the parts store you can use the blind door module same one I just replaced mine that’s how I know yours truly Robert r

Same as above. I created a video explaining what I did. Summary - passenger side actuator is for temp control. Drivers side actuator controls direction of air flow. Might be a little rough and tight to get to the drivers side actuator but once it gets done, you'll be SOOO relieved it's working. (PS - here's my video - https://www.youtube.com/watch?v=KY8-B5GFRus&t=2s )