Just noticed that my new (to me) H3 Alpha gives me no heat. A/C works great, but the temp dial doesn't change anything and I continue to get cold air. Can anyone point me in the right direction?

 

It will get fixed in the upcoming recall campaign for H3 HVAC controls ..... its warm in CA, nothin to worry about.

two places:

https://www.hummerforums.com/forum/h...p-28289/page4/

The pics are gone from this one... https://www.hummerforums.com/forum/h...wer-fix-19208/

 

Check your coolant level first.

 

Thanks for that link. I actually found that in a search, but disregarded it after reading the first page since it seemed to be a different problem; it talks about 1 notch of cold and then every other position hot. Mine is always cold no matter what position, never hot. After your reply/link, I read further and see several issues addressed, from the blower motor to the temp control.

Hopefully the upcoming recall will fix my issue, although I'm kinda under the impression that it would only address the blower motor? I certainly am not going to agree to a $400 control replacement if a $2 resistor will suffice.

Thanks for the help; I'll be watching for more info.

 

Coolant level is good.

I also get, just sometimes, a kind of clicking noise from behind the center panel. Sounds like a gear skipping teeth; likely the motor/controller that operates the door for the hot or cold air?

 

OK, I'm really getting frustrated. To be honest, I have not installed the 68ohm resistor in the wire (yet) although I have purchased it. But, I really don't think that's my problem. There are 2 actuators under the dash that operate trap doors related to the temp control (there is another one above those 2, but it operates the output (dash, defrost, floor, etc). Every time I start my truck, both of those actuators "try" to rotate, but can't. You can hear (and feel) chattering as the gears skip. After about 10-15 seconds they stop (give up?). I have pulled both actuators off; when removed from the HVAC system but still plugged in, they seem to work "most" of the time, but even then occasionally chatter, although when I disassembled them I can find no worn teeth. Physically/manually operating the trap doors using a large screwdriver is possible, although a bit stiff; I'm just not sure how stiff is normal. I can get the actuators online for about $20, or $30 at Autozone, but I really hate to throw money at it unless I'm sure it will solve the problem. And if it's something binding inside the HVAC sytem...I don't even want to think about how expensive that would be just to get to!

Any suggestions/words of encouragement?

 

Did you try to recalibrate your hvac unit?

If not the procedure is with the ignition on engine off.

1) turn temp **** all the way right.
2) turn fan speed all the way right
3) turn position selector all the way left.
4) press and hold both the ac button and the rear defrost button untill all three ac lights start blinking.

It will cycle thru all positions and temp settings then stop blinking.

 

Yup, tried the recalibration several times. Since they won't/can't rotate, the calibration doesn't work. I still have no heat at all, just cold. Over the weekend, I put the 68 ohm resistor in; made no difference. I guess I'm going to have to buy a couple of new actuator motors and keep my fingers crossed.

 

same problem. Has anyone resolved this issue of no heat?

 

And digging up Old As Dirt Thread to ask a question….. People are pointing and laughing at you. Skip the necro-bump and just ask you question after using “search”.