2017 Yukon A/C vent issues hot/cold

Disclaimer: Links on this page pointing to Amazon, eBay and other sites may include affiliate code. If you click them and make a purchase, we may earn a small commission.

solson96

TYF Newbie
Joined
Oct 23, 2022
Posts
8
Reaction score
3
Hello new member thank you for the add. I have a 2017, and we have had an issue when the air is put on the face it blows moreso on the feet. So much so I gave it to my wife practically brand new. In the TX heat I need all the air on my face! Now recently when the air is on now the middle and back vents blow hot. If I lower the rear temp and push the auto button it will turn cold. When the kids are cold I raise the temp and the heat comes back. Any ideas? Some say a control module and others blend doors. Just wanted to get ideas and how hard it might be. Thank you in advance!
 

Joseph Garcia

Supporting Member
Joined
Aug 2, 2018
Posts
6,386
Reaction score
8,310
Welcome to the Forum from NH.

Lots of knowledgeable folks here who freely share their knowledge, experiences, and perspectives. Knowledge is power.

I hope that you will become a participating member in the Forum's discussions.

Pics of the truck, please.

I cannot personally help you with your question; however, other members on this Forum that are much more knowledgeable than me will chime in.

@swathdiver
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,097
Reaction score
25,021
Location
Treasure Coast, Florida
Hello new member thank you for the add. I have a 2017, and we have had an issue when the air is put on the face it blows moreso on the feet. So much so I gave it to my wife practically brand new. In the TX heat I need all the air on my face! Now recently when the air is on now the middle and back vents blow hot. If I lower the rear temp and push the auto button it will turn cold. When the kids are cold I raise the temp and the heat comes back. Any ideas? Some say a control module and others blend doors. Just wanted to get ideas and how hard it might be. Thank you in advance!

It could be either, you need to find out what the internal trouble codes are. If you have Onstar, they might be able to tell you. Otherwise, you'll need a bi-directional scan tool to pull the BCM codes. Either the controller is on the fritz or it could be the mode actuator.

The mode actuator is in the driver's footwell and replacing it isn't too difficult a task. The controller is easy to change out as well. However, a new one requires it to be programmed.
 
OP
OP
S

solson96

TYF Newbie
Joined
Oct 23, 2022
Posts
8
Reaction score
3
It could be either, you need to find out what the internal trouble codes are. If you have Onstar, they might be able to tell you. Otherwise, you'll need a bi-directional scan tool to pull the BCM codes. Either the controller is on the fritz or it could be the mode actuator.

The mode actuator is in the driver's footwell and replacing it isn't too difficult a task. The controller is easy to change out as well. However, a new one requires it to be programmed.
Ok thank you! I have a crappy code reader and it read B1011, U0121, and U0140. The last two are lost comms with ABS and Body control module. If it is the controller how could I get it programmed, a specific program and tool?
 

swathdiver

Full Access Member
Joined
May 18, 2017
Posts
19,097
Reaction score
25,021
Location
Treasure Coast, Florida
Ok thank you! I have a crappy code reader and it read B1011, U0121, and U0140. The last two are lost comms with ABS and Body control module. If it is the controller how could I get it programmed, a specific program and tool?
The first also refers to a communication problem. Are these active or historical codes? How old is your battery? Do you think it was unintentionally discharged too much recently, such as leaving the radio and lights on with the engine off?

Programming for yours requires a bi-directional scan tool like the MDI2 connected to a laptop with a subscription to ACDelco's TDS system. You could also subscribe for a short time to their GDS2 software for diagnostics with the scan tool.

You can subscribe to the shop manual at AllDataDIY and other places as well to use the troubleshooting guides.
 
OP
OP
S

solson96

TYF Newbie
Joined
Oct 23, 2022
Posts
8
Reaction score
3
Ok thank you! I have a crappy code reader and it read B1011, U0121, and U0140. The last two are lost comms with ABS and Body control module. If it is the controller how could I get it programmed, a specific program and tool?
?hash=cfb9794664bd60e931e1de4f1f614e7d.jpg
 

Attachments

  • thumbnail_IMG_2034.jpg
    thumbnail_IMG_2034.jpg
    293.9 KB · Views: 3
  • thumbnail_IMG_2037.jpg
    thumbnail_IMG_2037.jpg
    216.9 KB · Views: 3
OP
OP
S

solson96

TYF Newbie
Joined
Oct 23, 2022
Posts
8
Reaction score
3
I got the new actuator but it will not seat down enough for the screws to go back down into the housing. There is a gap too big to even start one where I was hoping it would suck it in all the way but I dont want to crack it. Any ideas why this might do that? I tried putting the old one back on but it was the same thing! Murphys law kicked in when I said oh this will be R2, remove and replace as we used to say in the air force!
 

Tahoe14

Full Access Member
Joined
Jun 10, 2014
Posts
1,682
Reaction score
894
Location
Central Fl
Did you verify that it was the correct part and part number, Does it have to go in a certain way to make sure it seats properly, maybe a youtube showing R&R.
 

Forum statistics

Threads
128,781
Posts
1,805,301
Members
91,760
Latest member
MyCleftNut

Latest posts

Top