NO AIR coming out of vents (ac/heat)

[jbluemke]

I am ridiculously frustrated right now. I have enough going in with this truck and my fn life. I'm about to lose it.

Among my many other 2007 denali issues...... NOW, no air is blowing out (no AC, NO HEAT.....nothing at all).

Does anyone know what the issue might be. How hard is it to fix, etc etc. (Have a power steering leak but just topped it off, the temp gage is fine). My step sons went to use it yesterday and WALLAH..... no air when I use it today.

I'm about to freaking lose it.

 

[Tozan]

Can you hear a fan running?
Did you check the fuses?
Is the rear AC unit blowing air?

 

[jbluemke]

No fans running AT ALL.

I havent checked the rear AC. (What does it mean if it is and/or isn't?)

And I havrnt checked the fuses (you dont by any chance know which one(s) it might be? I'm at work (and was on break at the time sweating my @ss off)

 

[Tozan]

If the rear is working and the front is not then you might be able to isolate your search on just the front fuse, circuits or motor if both are not working then it might be something that is controlling both units.

Someone can correct me if I am wrong but, I am not sure which fuse box they are in there is a fuse box by the driver door and one under the hood. I think the fuses are labeled on the fuse covers.

 

[rockola1971]

If you have automatic climate control (Digital readout for temp settings) and all fuses are good then your resistor module for the fan likely went out. It is underneath your glove compartment in the air duct. You will see it immediately when you drop the plastic cover down from underneath the dash passenger side. It will have a wiring harnes plug into it and then a 2 wire harness running over to the blower fan. Could also just be a bad blower fan too.

 

[Fless]

Once you have access to the blower motor connector you can apply fused 12vDC to the connections to see if it runs.

 

[Fless]

No fans running AT ALL.

I havent checked the rear AC. (What does it mean if it is and/or isn't?)

And I havrnt checked the fuses (you dont by any chance know which one(s) it might be? I'm at work (and was on break at the time sweating my @ss off)

Underhood fuse block, check J-case fuse #73. And download the owner's manual from GM's web site.

 

[jbluemke]

Yes, my rear seems to be working (not much cool air but it blows).

What types of fuses do i need when I try to replace these fuses?

 

[jbluemke]

And how hard (and expensive) are the resistor module and the fan blower motor ?

 

[jbluemke]

And when I check if a fuse is bad..... It will have a broken connector wire, correct? Or is there more to it? Sorry, I'm not that experienced

 

[Fless]

You can watch the whole thing, or from where it starts. He shows how to test a J-case fuse with an ohmmeter. You can also use a visual test but those aren't always absolutely accurate.

 

[Doubeleive]

it used to be on the previous models the fan blower motor resistor would go bad and then you would get a variety of problems, no fan at lower speeds, or fan on when key off, or any combination. now on the gmt900's they overbuilt the resistor and I don't see any complaints of them going out, so that being said "IF" a fuse blew there is a reason why, I would start with checking the fan motor, if you do not have any technical tools or skills then I would just remove it and apply 12v directly to the motor to test it or if you can run a couple wires to the motor connector, to get access to it you will need a 7mm deep socket, it is under the passenger side kick panel under the glove box, there are lots of youtube videos showing how to replace the actuator the fan is right next to it and it is in the same location for like 20+ years now.