Duramax HVAC..... I'm stumped

CHOP SHOP · Dec 29, 2011

skinny_pedal said:
Better plan on keeping it forever because technology is only getting worse for the diy guy. I know manufacturers ultimate goal is so the average guy can't work on his rig.

Ive had my trusty ol 12 valve down to nothin. Easy to fix, tough to replace.

500,000 is my goal.

crash2 · Dec 29, 2011

CHOP SHOP said:
Ive had my trusty ol 12 valve down to nothin. Easy to fix, tough to replace.

500,000 is my goal.

I won't argu--good rig for sure. But all vehicles have there inherent problems and I see way more than most on the gm line....

zukkev · Dec 29, 2011

Ya'll shoulda bought a Ferd!!! :fawkdancesmiley:They Neeeevvver have any issues you speak of here!!! :redneck:

Clark · Dec 30, 2011

I am going to replace the hvac panel. Is there some kind of reporgramming i need to do to the BCM or to the panel to get it to work?

Clark · Dec 30, 2011

Would the digital one swap inplace of my "manual" one? Or is there more to it?

johny5 · Dec 30, 2011

crash said:
There is a problem with the clusters.

One of your heating elements is bad.

Is there a way to test the gauge to find out if its not the sending unit .

crash2 · Dec 31, 2011

johny5 said:
Is there a way to test the gauge to find out if its not the sending unit .

You can check the data and verify. But none of the guages are hard wired to the cluster. They are known as "smart clusters" and have there own processing ability. Information for the guages is sent by certian modules via the class 2 data line.

crash2 · Dec 31, 2011

Clark said:
Would the digital one swap inplace of my "manual" one? Or is there more to it?

I'll check on that clark...

Rcbro · Dec 31, 2011

I've replaced one of the HVAC clusters with the same issues as you described, when I removed it you could see the board had a burnt section in it. Just for kicks I pulled the one out of my truck and swapped it in. Problem went away.

As for the gauges, mine is currently not working (speedo, tach and oil pressure) the recall was in place for 7 years or 80,000 from original purchase. I'm just past both as mines an 04. You can get a refurbished one on eBay with a core for $250 or send it to the place for $150. Both have a warranty. That is the cheapest I can find.

ain'tstuckjustresting · Jan 1, 2012

Tacoma speedometer rebuilt my cluster. Dropped it off and it was done 2hrs later. Good folks.

Zoediak · Jan 1, 2012

ain'tstuckjustresting said:
Tacoma speedometer rebuilt my cluster. Dropped it off and it was done 2hrs later. Good folks.

yeah those guys do decent work...

on my 'o5 mustang i had, the speedo went out, which was a know servo failure issue... i just ordered up new updated servos for like $5 each and replaced them.... easy peasy, took about 15 minutes after removal to replace speedo and tach servos... saved $260 and up at the dealers..

unrelated, i know, but... it was fun...

took me back to the days of being electronics tech.... ahhh the memories

Clark · Jan 30, 2012

CRASH- I got a letter from GM regarding some kind of resistor in the manual HVAC trucks, and they will fix it for free. Could this be my problem?

Or is that only related to the blower fan, and not the climate control, heat, vents, A/C, rear defrost all not working?

It sounds too good to be true, and i'm still limping it with no defrost.

Thanks Mike! I appreciate your help.

crash2 · Jan 30, 2012

Clark said:
CRASH- I got a letter from GM regarding some kind of resistor in the manual HVAC trucks, and they will fix it for free. Could this be my problem?

Or is that only related to the blower fan, and not the climate control, heat, vents, A/C, rear defrost all not working?

It sounds too good to be true, and i'm still limping it with no defrost.

Thanks Mike! I appreciate your help.

Thats for the blower only Clark. Its a replacement of the connector and resistor assy if the connector is melted..

I have done a couple dozen...

Clark · Feb 6, 2012

Thanks, i thought it was too good to be true. Usually is.

Clark · Mar 4, 2012

Finally got this fixed, it was the heater control panel, got a new one from budget truck in auburn $75.

johny5 · Mar 4, 2012

are you getting heat right away (when truck is up to operating temp)

Mine takes a few min to change temp.

On another note I did fix the gas gauge . The sending unit broke free from the mounting bracket and spun and was pressing up against the side of the tank