No airflow from the panel outlets

[Duraswede]

it was the hottest day so far yesterday and of course the ventilation broke down.. i stopped to fill the tank and when i started it up and drove away it suddenly stopped blowing from the panel vents, i tried every setting on the control panel but nothing happened, only the recirculation worked, and the air is now blowing up to the windshield and down on the floor.. but if i turn off the engine and start again then there will come air from the panel for a few seconds.. is there vacuum actuators like my old K10 -83 or is it electronic motors that control the air flow?
the strange thing is that it comes air the first seconds and then it closes the vent duct.. so the actuator must be working.. it sounds like an electronic fault :(:(:(
what do you think, is it something that has happened to someone before?

i have the electronic climate control with dual zone temp.
the truck is a -03 sierra 3500

[Johnny Cetane]

They're electrical. Believe it or not I've seen this issue fixed by just unplugging your HVAC controller and reconnecting it after 5 minutes. Give it a shot.

[Duraswede]

They're electrical. Believe it or not I've seen this issue fixed by just unplugging your HVAC controller and reconnecting it after 5 minutes. Give it a shot.
Thanks for that!! i will definitly try that tomorrow, computers work in mysterious ways so i wouldn't be surprised if that helped!!

[richp]

Hi,

So where would a fellow find the HVAC controller on his '01 K-2500 DMAX, if he had a problem like that?

Thanks.

Rich Phillips
Member #27

[DmaxMaverick]

Hi,

So where would a fellow find the HVAC controller on his '01 K-2500 DMAX, if he had a problem like that?

Thanks.

Rich Phillips
Member #27

In the dash. It's the control head the buttons and dials are attached to. Once you pop loose the dash bezel, it's pretty self explanatory. Very simple. But, no logic involved on a 2001. Disconnecting it will only serve to correct a possible poor connection.

[richp]

Hi Dmaxmaverick,

Thanks. Other than checking that connection, do you have any other ideas about what would cause intermittent operation of the air conditioning on an '01?

At first, I attributed it to ice formation in our humid climate, but that's not it.

Thanks.

Rich

[Duraswede]

No, that didn't helped.. i tried to disconnect it with the ignition off at first but it was the same when i turned it on again, so then i disconnected it with the ignition on but neither that helped..
i can hear the actuator operating when i turn on the ignition, it starts blowing from the panel outlets but after a while it closes, it's obvious that this is a electronic fault, i hope that i dont need to replace the controller..
is there any potentiometer on the electric actuator?n mayby it's giving false signals.

[DmaxMaverick]

Hi Dmaxmaverick,

Thanks. Other than checking that connection, do you have any other ideas about what would cause intermittent operation of the air conditioning on an '01?

At first, I attributed it to ice formation in our humid climate, but that's not it.

Thanks.

Rich

More often than not, it's just over or under charged. The control head has no function with cycling or "intermittent" operation, unless it has connection/switch issues. The pressure limit switches could need attention, but they're on the high and low pressure circuits under the hood (not a likely cause). You need to get a gage on it to see just what's happening when it starts to not work. If you've never had to service the system, it's probably undercharged. A "Walmart tune-up kit" will fix it up, if that's the case. If you go this route, be sure to get the kit with a gage and follow the instructions carefully.

If the pressures check OK an you still have the problem, I have a spare control head I can loan you to eliminate it. I added heated mirrors to my truck, and needed the head with the rear defog button to make them work, so I still have the original head. If you have rear defog, the head will work. The defog will just be inop with it attached, which I don't think is an issue this time of year.

[Duraswede]

does anybody know where the actuator for that door is located? is it easy to acess undernearth the I/P?

[richp]

Hi Dmaxmaverick,

Been out of town and missed your reply.

That's where my thinking has sort of been drifting as well. 7 years old and never a complaint out of the system, so it's entirely possible I've got a small leak or something developing.

Appreciate the help.

Rich

[DmaxMaverick]

Hi Dmaxmaverick,

Been out of town and missed your reply.

That's where my thinking has sort of been drifting as well. 7 years old and never a complaint out of the system, so it's entirely possible I've got a small leak or something developing.

Appreciate the help.

Rich

If you go the "Walmart kit" route, get the kit with a gage and leak sealer/detector. I had to do mine about 2 years ago. Less than 20 bucks spent and it will freeze me out on 110° days. Don't get one of those "compatible" kits. Get the real stuff your system was designed for, even if it's a couple bucks more.

[Duraswede]

believe it or not, but today i got fresh air from my outlets!! i have to thank my father for that! he always says that he is very lucky to have a son that knows a lot and so on, but i could'nt believe it when he said that he had fixed my climate control:eek: he borrowed my truck to put he's boat down in the lake, and when he came back the HVAC was working normally! so he didn't actually "fix" it but without him it havn't worked.. so sometimes it's good to have a father! (uhhm.. last time he borrowed one of my vehicles he came back with a flat tire and a damaged rim:rolleyes:)
i hope that it won't break down again but then i know how to fix it;)

[ccurran]

It may be too late to help you, but in case others need the info:

After replacing batteries, I reset my A/C controller as such:

1) Start truck
2) A/C comes out defrost - wait about 10 to 15 secs
3) A/C then starts coming out the floor vents for about 5 seconds
4) A/C then starts coming out the dash vents.
5) While the A/C is coming out the dash vents, turn A/C OFF (otherwise it cycles back to defrost for good).
6) Turn truck OFF

Restart truck, A/C will work fine. This has been tested multiple times on my truck (05 2500 dmax) and a few others with similar A/C problems (hot on drivers side, cold on passenger).

Yea, I figured this out on my own... :)

cheers & beers,
Chris