C6 hvac control module replacement
#41
Instructor
Alright, I finally got around to replacing mine as work and weather finally permitted. Replacing the blend door actuator DID NOT solve my issues. There is no change in my symptoms, even after disconnecting the battery for a few. Any further assistance is appreciated. I really do not want to take it to a dealer.
#42
Melting Slicks
Damn. Sorry to hear that, but at least it wasn't expensive.
How about finding someone (like an independent shop) with a Tech II scan tool to pinpoint the precise cause of your issue. That's what I did, pointing to the Mode actuator as I discussed above. A dealer could do it too, of course, but that's such a PITA.
How about finding someone (like an independent shop) with a Tech II scan tool to pinpoint the precise cause of your issue. That's what I did, pointing to the Mode actuator as I discussed above. A dealer could do it too, of course, but that's such a PITA.
#43
Instructor
When I bought the car, I had a PPI done which included a scan. I have these posted on another thread, but I'll do so here as well:
The only symptoms my car exhibits are the HVAC issues described in this thread. But now I'm leaning towards a BCM issue although it's again just a guess.
The only symptoms my car exhibits are the HVAC issues described in this thread. But now I'm leaning towards a BCM issue although it's again just a guess.
#44
Melting Slicks
I'm not sure what I'm looking at with those pages of scan info. Are all those check marks Error Codes? They all look to be History codes, including the 0419. If you didn't show an active B0248, then the problem wouldn't be the Mode actuator that you replaced. What did that scan actually say was an Active code?
I had three other History Codes due to the Active B0248.
I had three other History Codes due to the Active B0248.
#45
Instructor
None of the codes show as active, most are pending. But based on the symptoms, it has to be something electrical. You claim to have had the same symptoms which were alleviated by replacing the blend door actuator. If my replacing it did not solve the issue, then I’m led to believe that whatever is controlling it has an issue whether it’s the BCM or the wiring itself. That’s really all I can think of. It may also explain the other random codes regarding the door modules.
#46
Melting Slicks
Good point. But "it has to be something electrical" can mean anything on these cars, and not at all about 12 volts. Sensors, modules, computers....that ain't "'lectrical", but I know what you mean.
I would suggest you find a sympathetic person with a Tech II tool, and an hour of time (offer $100--worth it), and with the Service Manual in hand, and with what you now know about this problem vs. what you didn't know last October to try crack what's going on.
I would suggest you find a sympathetic person with a Tech II tool, and an hour of time (offer $100--worth it), and with the Service Manual in hand, and with what you now know about this problem vs. what you didn't know last October to try crack what's going on.
#47
Racer
Thread Starter
Ok...I finally was due for an oil/filter change. And I paid to have Partyka hook up their $5K dealer level scan tool and do a full diagnostic. As I feared, it's a bad flow door actuator. Appears most of the dsahboard had to be removed to access a $174 part. Total cost is about $2K. Otherwise, the HVAC module was functioning normally. A good thing as I think they're $900 or more.
Wonder what this would cost in a Porsche, McLaren, Lambo, Ferrari....
Anyway, I believe this is pretty close to the cost of a clutch replacement.
On the other hand, this is the first REAL repair needed in about 6 1/3 years of ownership since new. Comes to about $315/year. Probably chump change compared to the above...
My biggest fear...That everything is put back to factory. No squeaks, rattles, buzzes and leaks. So far, they've done well by me. I'll have to keep my fingers and toes crossed....
Wonder what this would cost in a Porsche, McLaren, Lambo, Ferrari....
Anyway, I believe this is pretty close to the cost of a clutch replacement.
On the other hand, this is the first REAL repair needed in about 6 1/3 years of ownership since new. Comes to about $315/year. Probably chump change compared to the above...
My biggest fear...That everything is put back to factory. No squeaks, rattles, buzzes and leaks. So far, they've done well by me. I'll have to keep my fingers and toes crossed....
#48
Melting Slicks
What do you mean by a bad "flow door" actuator? Do you have those codes?
There are four actuators for these four doors: Recirculation Door (above the passenger's right knee, and easy to replace). Left Air Temp Door. Right Air Temp Door. And finally, the Mode Door, which is the actuator that I replaced in my discussion above, which is DTC B0248. That actuator is $33 at Rock Auto.
I'd need more exact info on your situation, but if you're letting them rip into your dash for anything other than the Temp Doors, I think you're making a mistake. If it is your Mode Door Actuator, and if you're not a DIY kinda guy, you should find a handy independent mechanic who would follow my How-To. It would take him an hour, maybe 90 minutes.
There are four actuators for these four doors: Recirculation Door (above the passenger's right knee, and easy to replace). Left Air Temp Door. Right Air Temp Door. And finally, the Mode Door, which is the actuator that I replaced in my discussion above, which is DTC B0248. That actuator is $33 at Rock Auto.
I'd need more exact info on your situation, but if you're letting them rip into your dash for anything other than the Temp Doors, I think you're making a mistake. If it is your Mode Door Actuator, and if you're not a DIY kinda guy, you should find a handy independent mechanic who would follow my How-To. It would take him an hour, maybe 90 minutes.
#49
Instructor
Please post your codes too if you have them. My issue is still not solved, but once I replace my AC compressor (clutch fell off not long ago), my next plan is to replace the BCM. My codes are posted further up in this thread.
#50
Racer
Thread Starter
This is definitely showing how little I know about this. Of course, the SA at the dealership didn't want to drop too much candy on the floor. I think she's assuming I'll come back as I've been there quite a bit. The SA I normally deal with was AWOL. This SA, I think is trying to squeeze me for the Gild.
That being said, you've encouraged me to seek a 2nd opinion. Problem is, I don't trust many indi shops around here. I know of RepairPal.com. I've used a site called Home Advisor with decent success. I might look on their site and see who I can go to near me. The worst case repair bill the site gave me on this, was $600. So, you may be right. Thing is, can the actuator motors be purchased separately? Or must an entire unit be purchased. On a Ferrari with a F1 steering wheel, if a plastic button breaks, you have to buy the ENTER steering wheel...for a piddly $5K...
That being said, you've encouraged me to seek a 2nd opinion. Problem is, I don't trust many indi shops around here. I know of RepairPal.com. I've used a site called Home Advisor with decent success. I might look on their site and see who I can go to near me. The worst case repair bill the site gave me on this, was $600. So, you may be right. Thing is, can the actuator motors be purchased separately? Or must an entire unit be purchased. On a Ferrari with a F1 steering wheel, if a plastic button breaks, you have to buy the ENTER steering wheel...for a piddly $5K...
#51
Yes, you can get just the needed part, and more than a few write up going through the glove box opening to work on the external part of the air box (so you don't have to pull the dash)..
#52
Instructor
Ya you definitely don’t have to pull the dash. I’m not too mechanically inclined and I replaced the blend door actuator in about 45 minutes, just follow the referenced write ups. You need a drill and a socket and extension.
#53
Melting Slicks
This is definitely showing how little I know about this. Of course, the SA at the dealership didn't want to drop too much candy on the floor. I think she's assuming I'll come back as I've been there quite a bit. The SA I normally deal with was AWOL. This SA, I think is trying to squeeze me for the Gild.
That being said, you've encouraged me to seek a 2nd opinion. Problem is, I don't trust many indi shops around here. I know of RepairPal.com. I've used a site called Home Advisor with decent success. I might look on their site and see who I can go to near me. The worst case repair bill the site gave me on this, was $600. So, you may be right. Thing is, can the actuator motors be purchased separately? Or must an entire unit be purchased. On a Ferrari with a F1 steering wheel, if a plastic button breaks, you have to buy the ENTER steering wheel...for a piddly $5K...
That being said, you've encouraged me to seek a 2nd opinion. Problem is, I don't trust many indi shops around here. I know of RepairPal.com. I've used a site called Home Advisor with decent success. I might look on their site and see who I can go to near me. The worst case repair bill the site gave me on this, was $600. So, you may be right. Thing is, can the actuator motors be purchased separately? Or must an entire unit be purchased. On a Ferrari with a F1 steering wheel, if a plastic button breaks, you have to buy the ENTER steering wheel...for a piddly $5K...
C'mon man....stop whining, make some decisions, and get your car fixed. It's up to you now.
#54
I have a 2012 and am having similar problems. I am not getting any air from center console vents and the additional air is coming through the vents directed on my windshield fogs up the window when the a/c is on. I had the codes run and got active error codes of B0269 and B0419. B0269 is identified as "Air Inlet Door Range Error". The mode door actuator originally seemed like the problem, but from the discussion in this thread that would have been a DTC B0248. I am seeing B0248 in the history, but not active. Since my problem is in both center console vents, I am not sure what actuator, if any, would be causing the problem. Any suggestions would be appreciated.
#55
Melting Slicks
I have a 2012 and am having similar problems. I am not getting any air from center console vents and the additional air is coming through the vents directed on my windshield fogs up the window when the a/c is on. I had the codes run and got active error codes of B0269 and B0419. B0269 is identified as "Air Inlet Door Range Error". The mode door actuator originally seemed like the problem, but from the discussion in this thread that would have been a DTC B0248. I am seeing B0248 in the history, but not active. Since my problem is in both center console vents, I am not sure what actuator, if any, would be causing the problem. Any suggestions would be appreciated.
Again, my codes were.....
B0248--Airflow Control 3 Circuit (this was an active code, the others were "historic")
B0268--Airflow Control 7 Circuit (historic)
B0269--Temp Control 1 Circuit (historic)
B3748--Air Flow Control 3 Feedback Circuit Range/Performance (historic)
......and the problem proved to be the Mode Door actuator (0248). With that actuator not working, it caused the other historic codes, particularly codes 0268 and 0269 which points to the Recirc/Air Inlet actuator. In my case, that actuator was fine and worked perfectly once I replaced the Mode Door actuator.
I think you have the opposite (but similar) scenario. Your Recirc/Air Inlet actuator is bad, which causes communications haywire with the other actuators and the control module, setting those historic codes.
As I mention in my write-up, getting to that actuator is a cinch, located above and to the right of the glove box. Once you pull the glove box and peer up there, it's easily seen. If I'm wrong, you've wasted $30 and 30 minutes time. But if I'm right.......
#59
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!
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!
My problem is the the two right most buttons, front and rear defrost, do not move at all so I can't turn on either defrost. I'm guessing that the only fix for that is a new control module. Can any of you who are much more savvy than me ;-) please advise?
Thanks!
Last edited by rickc519; 11-10-2020 at 03:33 PM.
#60
I know I'm responding to an old post but I'll take a shot. My problem is that the 2 defrost buttons on the right don't move at all, it's like they're glued in place. All the others seem to work fine. Are you saying that potentially the buttons themselves can be repaired and not necessarily the whole unit?
It's expensive but it looks like replacing the unit isn't overly difficult.
It's expensive but it looks like replacing the unit isn't overly difficult.