HVAC controls

[SuperBuickGuy]

Is there a computer that controls the HVAC in an H3? is it located in the controls?... I think part of the problem in fuel economy is my a/c compressor never shuts off - when I have the control to "floor heat" I get a/c cool air.... add to the issues that something is staying on and killing the battery (24 hours to dead), and it's time to start solving some gremlins.

 

[Happy Hummer]

It's seems to be the norm now. The tj I had before this h3 had the same a/c running continuous and you had to install a toggle switch and wire so as to defeat it.
No experience with over riding in h3 though.
As for the gremlin gf's h3 is notorious for this issue. Heated seats accidentally left on or hac nob left on battery is dead. Radio plays even when doors open. Lol.
I've chased gremlins and gave up. We make certain all these items are off at all times. Another item is her key lock assembly on ignition don't always turn completely to off either.
It's a great ride but finicky.

Chris

 

[amrg]

Is there a computer that controls the HVAC in an H3? is it located in the controls?... I think part of the problem in fuel economy is my a/c compressor never shuts off - when I have the control to "floor heat" I get a/c cool air.... add to the issues that something is staying on and killing the battery (24 hours to dead), and it's time to start solving some gremlins.

When I had my H3 hooked up to hptuners there was an option that lets you disable A/C compressor at desired throttle percentage/RPM value and re-enables it when you drop below specified values. Other than that I didn't see any other options you can use. (either that or there is something hidden/hptuners isn't deep enough to control everything or there are no settings at all)

 

[Best4x4]

And you had both the snowflake & Recirculate off correct? I know the AC Compressor will come on in any defrost mode no matter what the LED settings, but it should be off for the floor position. Now if you're running the Pontiac HVAC Control Unit the Recirculate function is backwards. LED on = not on Recirculate LED, off = Recirculate.

 

[SuperBuickGuy]

nope, recirculate is not on...

I'm fortunate that I've had 2 H3s, so the comparison is to the prior one... the control has some kind of short in it because one knob light works most of the time - but I really don't want to spend $300 blindly.

as for the battery issue, on my 06 GTO the dealership had to replace the ecm because it wouldn't shut down and killed the battery. As this does this issue every time, it really is a matter of putting my tester between the negative terminal and the chassis (removing the wire, obviously) then start pulling fuses.

 

[Best4x4]

I was able to grab an entire center bezel for an H3 from LHQ complete with the AC Vents, HVAC Control Head, 4x4 Controls, Aux Power Ports, and rear wiper control for 90.00 with free shipping!!! I think they had one listed on their Ebay site the other day for like 150.00 complete with everything. I bought mine for the two AC Vents (one on my wife's was broken from a previous owner), and figured it was smarter to get that vs just 2 AC Vents from the dealership! I also did the resistor fix on my wife's H3 and I can actually control the temp now vs cold then 3 clicks and full heat.

I've had those HVAC Control Heads apart and I can tell you the Pontiac version is programmed differently. Not only is the LED for recirculate different, but it runs the compressor more and in our H3's it will eventually freeze it over. I bought 2 of them as they were cheap, and used them for the outer plastic parts (I like how they light up vs our stock units).