SHM

I did a search on YouTube and this site and I didn't see anything regarding replacement of the HVAC control module.

I looked up the price and they're big money. Probably the most expensive module in the car. About $700. GM Parts Warehouse does sell them for under $400, so If could do this job myself, I could probably save half what the dealer would charge.

Has anyone done this? How much of a PITA is it to do?

Thanks!

719c6

It's really not hard. Only pain in the **** is getting one of the plugs to disengage. There are several videos on removing center plastic. I've done it several times, changing radio, HVAC unit and other tweaks.

Check out the forsale forum here, that's where I got mine, really good deals there.

SHM

Thanks...I think I found a great video. I'm putting the link here so I can refer back to it. It's good enough where it's almost making me brave enough to attempt this. And thanks for the suggestion to search this site for the part. That's next.

https://www.youtube.com/watch?v=xDJT...E#action=share

And if you need to save this video to your phone, tablet, etc.

http://en.savefrom.net/1-how-to-download-youtube-video/

GREENKAR

I have done the swap also. It is pretty straight forward and fairly easy to do. Just take your time. Very

SHM

I just ordered the new controller module. I'm going to do it myself. Got it for $400 delivered from GMPartsHouse. RockAuto had it listed when I put in the part #. But, then removed it from my cart because they didn't really have it. Too bad. They wanted less than $300 for it.

Bill Soda

Be careful...I have purchased from RockAuto and they have some real cheap JUNK.

ben dover

^This^. Go slow and take pics of disassembly.

SHM

Rock had the module listed after I put in the part#. Then, when I went to the cart, a pop up said this part was not available and it was removed from my cart. Ok...that took care of that. So far, I've had good luck with them on brakes and filters...But, I only order OEM. If OEM isn't available, I won't put in anyone else's parts. Too much trouble in the past going aftermarket.

So I got the module from GMPartsHouse. $400 delivered. I could've gotten it from elsewhere for $10-20 less..But, I've dealt with them before and have had great luck in getting exact replacement parts that are hard to get except from the dealership.

SHM

I was able to download the total video of trim removal. The scariest part. The module is just held in by 4 bolts. And there are 3 keyed connectors in the back. Trickiest connectors are the cig lighter and flasher button.

See...I'm leaning already!

Dano523

Might want to back it up, and tell us the reason that you are replacing the controller in the first place.

Most of the time if you have a problem with it, it's just a cold solder joint on the board that just needs to be re-soldered to fix the controller.

Other times its the **** pots that have a problems, and they too can be replaced on the cheap as well (Mouser carries them, so just a matter of solder out the old one, and solder in the replacement). Hence the pots use a rubber cup piece as the return spring pressure on the very bottom of the inner assembly, and over time is just falls apart instead. So it not a matter of just pulling the pot apart to clean its internals, but finding the replacement cup to rebuild the pot instead.

So short of say the lettering on the buttons worn off that you can not just buy new buttons to rebuild the controller that way, most of the time it just a cold solder joint on the board that need to be re-soldered instead.

SHM

It started a couple of weeks ago. I noticed the fan was on high, but, the LCD display was showing slowest selection. When I pressed either button, the LCD would respond, but, no change in fan speed.

Then, I found the airflow selection buttons wouldn't change the flow direction through the ducts. Again, it would show changes in the display, but, the flow out of the vents didn't change. The temp control worked. Don't know if the a/c works as it's still winter here.

My belief is the quad drivers inside the module have fried....If that's how they control the fan and airflow door solenoids...

irok

that is much cheaper than a lot of the module's in the car.some of the EBCM's are $2,000. if you can even find one

SHM

I was watching a resto show 'The Gild' up in Canada..They were restoring a Astin Martin. One of the ECMs failed. The car uses 1 per cylinder bank. They have to be bought in pairs. $7k!!!

I understand owners of 1997 Vettes are having trouble getting replacement modules. Specifically the EBCM. And I've heard of Porsche like prices being asked for them...

One thing I will do that wasn't shown in the video is I'll use masking tape on the trim finished surfaces. I'm kind of clumsy and the tape will protect the shiny bits...

frankywi

I am trying to fix the worn out buttons on AC my head unit. I got a broken one for a few bucks and it has no wear on the buttons that I need. Once the 4 screws on the back are removed (brute force on the broken unit), the buttons are really easy to remove, without dealing much with electronic components.

I just can't figure out how to unscrew the four screws on the back of the unit nicely to take it apart. The screws appear to be hex bolts around 5mm. I can't use a (regular) socket because the screws are so close to the body of the unit that there is not enough space to stick it on the screw. I tried mini open wrenches but they just strip the head of the screw.

Any suggestions are very much appreciated.

Bingo002

Just to follow up, did you replace the module and solve this issue? I have word for word the exact same symptoms and want to know before I pull the trigger on a new one.

Tracy

Can you please provide some details on the location(s) of the cold solder problem, and also on replacing other components that you seem to know about (that also fail)? I'm a fairly good solderer, but I'd like to know where to apply my iron.

FiveVettes

I have a similar problem after parked in the sun for a while, after starting the lcd screen is blank for a few minutes or for as long as15 minutes. How does one find and repair a cold solder?

Tracy

Never mind....I just ordered a reman unit from ASI. No muss, no fuss. It'll be here in a few days...no hunting for the elusive cold solder issue that might or might not solve the issue.

$356 delivered.

SHM

My problem turned out NOT to be the HVAC control module. It turns out the A/C condenser took a odd stone hit and leaked out all the freon. I had that replaced at the dealership. That was less than half what a new controller costs. Good thing I have a dealership I can actually trust near me.

Tracy...Can you give a link to the place 'ASI' where you were able to get a reman controller? Might be useful in the future. Thanks!

Tracy

Here: https://www.autoecu.com/climate-cont...iABEgJy1fD_BwE

I did the swap and it didn't solve the problem, and I was able to return it to ASI because of cosmetic damage to one of the buttons that I called them about as soon as I opened the box the afternoon that it arrived....so they honored the return on that basis (and that basis only). Anyway, at that point I knew I had the other issues that have been discussed here many times. I have no control over the modes...just air from the main vents and wonky temp control. And wonky auto control. And other wonkies.

Also, the "pull HVAC fuse to reset things" maneuver did not work, nor did I really expect it too. Wishful thinking made me do it.

I found an indy shop (to avoid assholian dealership behavior) that had Tech II equipment and they pulled the typical codes that others have posted on this forum: B0248, B0268, B0269, and 3748 (inlet door range error). I'll have to study the FSM to learn which actuator I'm dealing with, etc, etc, etc.