I'm new here and have tried Searching but have had no luck. I have an 08 H2 and just like a bunch of others, I have A/C problems. It doesn't work unless I'm driving at like 30mph and up. Even then, it barely blows. It gets in the high 90s and low 100s where I live and I don't have any A/C. PLEASE HELP

 

Good luck. Its mid 90's in atlanta today- if my ac wasnt working i think i would bite the bullet and take it in for service. Good luck and hope its an easy/cheap fix.

 

A little more info would help. With the fan on max can you hear it blowing but still have very little airflow? If the fan's turning, is air coming out anywhere? Does the heater work fine or is it affected, too? With the hood open can you see the a/c clutch cycling or engaging? Details man, details!

 

Also just and F.Y.I. before my compressor was replaced I heard a loud noise when the A/C was on. It only lasted a couple minutes. Later I found that the compressor pulley had seized up and threw the A/C belt. Surprisingly the belt was still O.K. (I replaced it anyways in fear that it had stretched) but thought I would throw that out there. You do have a separate belt that runs the A/C. (I thought my serpentine belt ran everything) Maybe check that also.

 

sounds like a fan issue if your getting a/c at moving speeds. if it was a bad compressor it wouldnt blow cool at all. and if it was a low freon condition you would still get "cool" air at an idle just not cold or there would be a delay for it to get cool. with your a/c on you should be able to hear both of your fans running just standing in front of the truck. IIRC one fan will always run with the a/c on and the other fan cycles on and off when coolant temps reach a certain value. is your truck overheating at all?

when you turn the fan on high does it blow air? if its not blowing air then it could be the blower motor also.

 

This has happened to me since I got my 2008 2 months ago. AC works fine at first, ice cold air, on low or high it doesn't matter. Then after 40 30 minutes or so the air stops coming out of the vents but you can hear the blower going behind dash. If you have it on max it's really loud behind dash but no air from vents. **** off AC for 10-15 minutes put it back on and it works again but for a short while and then does same Thing again. Anyone have any ideas?

 

Any aftermarket installs by the po? Could be related. Even so it sounds like something is causing the blend doors to move to the closed position. No air coming out anywhere, defrost and side vents included? That sounds like the system is being told to shut off but nobody is talking to the blower itself. Weird.

Are any of the controls or buttons sticky on the control head? My rear controls were gunked up with soda from the po, causing things to stick and not work. Was a b***h getting it all cleaned but the rear controls work fine now. Only had our '08 about 6 months so still finding stuff like this.

 

Definitely something to do with the blow doors going to closed position. No air coming out of side vents either. I shut off the AC for 15 minutes turn it back on and it works for a little while then no more air but the blower is blowing cause you can hear it. All buttons like new.

 

I've rum into similar problems on vintage bikes I own where the solders were cold or just poorly done on a circuit board, causing intermittent problems like this. I would lean toward the control head. Tapping on it or pushing hard on the buttons, wiggling get at least temporary function? Sometimes applying pressure like that works long enough to at least confirm whether it's the head or not.

My '08 had been man-handled by the po; the clock and headlight switch were both pushed into the dash, likewise the 4wd switch and the rear a/c control head. Gorilla hands, I guess. But if I remember right I found a loose plug on one of the controls when I took everything apart to fix it. Might be as simple as that. Let us know what you find.

 

There is actually a recall on this for the H3's but not the H2's yet. Just a matter of time. I called Hummer and they said if I go to a Hummer dealer and get it fixed, whenever the recall comes out I will get reimbursed. Here is what I found on the forum:




Has the blower in yourhummer quit?
Does the AC light still come on but no air blows out?
Did you notice a burning smell just before the blower stopped working?

You may be a victim of a poor Generous Motors design for controlling blower speeds. With the technologyavailable when Hummers were first made, it seems strange that GM did notimplement a PWM system to control the blower speed in Hummers. That systemwould save energy, not produceheat like a resistor, to control the blower speed. It would have also allowedGM to put a continuously variable speed control on the Hummers for theircustomers, instead of a four speed switch.
Anyway, they didn’t do it, probably to save a few pennies per Hummer. So thoseof us who have had to put up with the failure of our blower system, have todish out big bucks for getting our blowers working again. The repair is not afix, because IT WILL FAIL again.
Now, you may be able to save those big bucks if you are half way handy with asoldering iron and a Dremel type tool. This may also prevent your blower speedcontrol from failing again.
I assume you know the H3 blower motor and wiring harness is located behind theglove box. Remove glove box to start thisproject. Remove right end cover to dashboard. Remove blower plug, remove whitegang plug, remove black gang plug, THEN remove resistor with connector attachedlast. Now take resistor and wiring harness to yourwork bench to start saving more money.
You may have to work to get the resistor removed from the connector as theburnt terminal inside has melted and fused the surrounding plastics together.Keep working at it, rock it back and forth, you will get it apart.
Now, does it look something like this?



Cut around the connector shield on the resistor to allow better access to theterminals. You can cut this with a Dremel type tool or with wire cutters like Idid.



Now you can use a file, sandpaper, or a Dremel Type tool to clean and roughenup all the resistor terminals. This will allow the solder to better adhere tothe terminals and give you a better connection. We don't want any cold solderjoints here.

A

Next, cut the wires behind the connector on the harness so as to get us intosome fresh, unburnt wire.



Take note of the wire colors and orientation at this point. We want all wiresgoing back to their original terminal.

Carefully solder each wire to its corresponding terminal, making sure yoursoldering iron is strong enough and hot enough to make a good clean solderjoint on each wire and terminal.



Reinstall the harness back into the vehicle first, and reinstall the resistorlast. This will prevent any excess strain and pull on the resistor terminals.
Turn the key on and enjoy your AC blower once again! And it cost you nothingbut time. If you made good solder joints, your blower should never fail again!