Anyone put in a remanufactured HVAC module?
05-19-2022, 05:59 PM
#1
Race Director
Thread Starter
Anyone put in a remanufactured HVAC module?
The HVAC dash module in my 2007 coupe is dying fast. Today it wouldn't blow cold air out the driver-side vents. Whether it works or not is a daily crapshoot. I'm inclined to put in a remanufactured unit from a company called Autoecu. Has anyone dealt with this company for a reman HVAC module? Used HVAC units are around $200 in eBay, and the reman one costs $429, but I'd rather do this repair only once and buying a used unit has little appeal. But, I'd like to hear from anyone who's used this company or another one and hopefully ended up with a reliable HVAC unit. Thanks ahead of time.
05-19-2022, 06:09 PM
#2
Melting Slicks
Looking at the same issue, same problem and same potential solution. I am looking at them also. I believe that company has a warranty on the units. One last trip to the dealer on Monday just to make sure it's not anything else, then I will be getting one of these. 
05-19-2022, 07:09 PM
#3
Drifting
When an HVAC control unit seems to be acting up, have you tried resetting it and recalibrating the ventilation mode door actuator before doing anything more drastic?
To reset the HVAC control unit:
Press both defroster buttons and the fan speed up button together, all three at the same time. Acts like a soft reset for the system.
To calibrate the HVAC ventilation mode door actuator:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC control module (HVAC/PWR SND 10A located in passenger side footwell).
3. Wait 60 seconds, then reinstall fuse. Important: The module memory will not clear if the battery positive voltage circuit fuse is reinstalled in less than 60 seconds.
To reset the HVAC control unit:
Press both defroster buttons and the fan speed up button together, all three at the same time. Acts like a soft reset for the system.
To calibrate the HVAC ventilation mode door actuator:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC control module (HVAC/PWR SND 10A located in passenger side footwell).
3. Wait 60 seconds, then reinstall fuse. Important: The module memory will not clear if the battery positive voltage circuit fuse is reinstalled in less than 60 seconds.
05-19-2022, 08:00 PM
#4
Race Director
Thread Starter
When an HVAC control unit seems to be acting up, have you tried resetting it and recalibrating the ventilation mode door actuator before doing anything more drastic?
To reset the HVAC control unit:
Press both defroster buttons and the fan speed up button together, all three at the same time. Acts like a soft reset for the system.
To calibrate the HVAC ventilation mode door actuator:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC control module (HVAC/PWR SND 10A located in passenger side footwell).
3. Wait 60 seconds, then reinstall fuse. Important: The module memory will not clear if the battery positive voltage circuit fuse is reinstalled in less than 60 seconds.
To reset the HVAC control unit:
Press both defroster buttons and the fan speed up button together, all three at the same time. Acts like a soft reset for the system.
To calibrate the HVAC ventilation mode door actuator:
1. Turn OFF the ignition.
2. Remove the battery positive voltage circuit fuse of the HVAC control module (HVAC/PWR SND 10A located in passenger side footwell).
3. Wait 60 seconds, then reinstall fuse. Important: The module memory will not clear if the battery positive voltage circuit fuse is reinstalled in less than 60 seconds.
This is something I've not heard of before. I'll give its a try tomorrow. Thanks for posting this obscure possible fix.
05-19-2022, 08:40 PM
#5
Melting Slicks
Member Since: Nov 2009
Location: Klein TX
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2023 C6 of the Year Finalist - Unmodified
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Good info, thanks for sharing. A couple of questions:
Do you perform the HVAC control module reset with the ignition and/or HVAC system on or off?
Which should you do first, the HVAC module reset, or the ventillaton door actuator calibration?
Do you perform the HVAC control module reset with the ignition and/or HVAC system on or off?
Which should you do first, the HVAC module reset, or the ventillaton door actuator calibration?
05-20-2022, 09:02 AM
#6
Drifting
Do the HVAC control module reset with the ignition on and the HVAC system on. I don't think the order matters with the HVAC reset and door calibration, but I suggest doing the HVAC reset first.
05-20-2022, 02:32 PM
#7
Race Director
Thread Starter
I just did these two procedures on my 07. The HVAC is working fine at the moment, but the problem is intermittent so I'll need to drive it a few times until I get any confidence that your fix worked, then report back. Thanks again or bringing up this possible simple fix.
05-20-2022, 03:15 PM
#8
Melting Slicks
Member Since: Nov 2009
Location: Klein TX
Posts: 3,037
Received 906 Likes
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2023 C6 of the Year Finalist - Unmodified
2022 C6 of the Year Finalist - Unmodified
Interesting stuff. I found two ways to do the door calibration in the shop manual. One with a Tech 2, the other without - fuse pull mentioned above. But I haven't found the module reset with the three buttons. Where did you learn about it?
05-22-2022, 09:22 PM
#10
Race Director
Thread Starter
I've started my C6 the past two morning to see if the HVAC readout goes crazy or not. So far, all is OK. Fingers crossed that Cloth Seats' procedures keep working.
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ClothSeats (05-23-2022)
05-24-2022, 10:51 PM
#12
Race Director
Thread Starter
05-25-2022, 05:45 PM
#13
Race Director
Thread Starter
When I started my 07 this morning there was a blank screen on the HVAC. After a few minutes the screen came online and I could adjust the temp. Later, when I restarted it all seemed to be OK, but after I adjusted the temps and set the fan to High it basically froze in those settings and I couldn't change the temps or lower the fan, which was on full blast. Looks like lI'll be an Autoecu customer real soon.