Hummer Forums - Enthusiast Forum for Hummer Owners - H2 AC only blows out Defrost Vents

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H2 AC only blows out Defrost Vents

Any help here would be appreciated.

After replaceing battery......A/C only wants to come out of Defrost vents and it is HOT in AZ.

I read some posts where people disconnected batteries again to fix...didn't work.

I read some posts where people removed ECM fuse....didn't work

I read some posts where people replaced Actuators...?

Sounds like there might be 3 actuators....how do you know which one to replace?

Mechanic wants $700 bones to "try" and fix....then went on Vacation b4 telling me which one and if there were any codes or not.

Thanks in advance for all your help.

Sounds like a blend door actuator.

Fix found for blend door issue.

Sorry for the above post it seems that I can't edit after I post :cool:

What I wanted to say is that I had a customer with this very issue and he just needed to recalibrate the actuators, it worked for him and I thought I would pass this information on to you to avoid costly un-needed repairs. Please review the attached PDF file and thank you again,

Troy Green
K&N Engineering
R&D / Warranty

It appears the file is too large, I'll post the text......

RE-CALIBRATING ACTUATORS

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.

Preferred Method (w/Scan Tool)
1. Clear all DTCs.
2. Place the ignition switch in the OFF position.
3. Install the HVAC actuator.
4. Connect all previously disconnected components.
5. Place the ignition switch in the RUN position.
6. With the scan tool, initiate the Motor Re-calibration feature of the Heating and Air Conditioning
Special Functions menu.
7. Verify that no DTCs have set as current DTCs.

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)
1. Clear all DTCs.
2. Place the ignition switch to the OFF position.
3. Install the HVAC actuator.
4. Connect all previously disconnected components.
5. Remove the HVAC B fuse for a minimum of 10 seconds.
6. Install the HVAC B fuse.
7. Place the ignition switch in the RUN position.
8. Wait 40 seconds for the HVAC control module to self-calibrate.
9. Verify that no DTCs have set as current DTCs.

Hope this Helps!

Troy.

What a Joke. I to was working on my 2004 H2, disconnected the battery and now it will only blow thru the defrost vent....SNAP !!!!!:eek:
seems you can read this problem all over the web, what gives ?

back outside to see what I can find................................:confused:

to get me by until I purchased a new actuator, a friend of mine repositioned the defective actuator so it was stuck on blowing air out of the vents instead of stuck on blowing air out the defrost. It was the actuator on drivers side, just above and to the right of accelerator pedal...then I sold truck without replacing it.

we are having the same issue...also in AZ. This is not good. have you tried that acuator yet??

Quote:

Originally Posted by Sarah Anglen (Post 345511)

What is "DTC's" ???

Diagnostic Test Codes