2017 Denali XL - No cold air in front (rear is cold) - blend door diagnostic?

[ShawnQ]

2017 Denali XL - 110k miles
Rear A/C is still ice cold, front A/C is room temp/ambient.

I have searched a handful of times and keep coming up with the same results. Sounds like I have a blend door issue.

What diagnostic tool can I purchase to diagnose this myself? I know some tools will actuate each blend door on command to verify if the actuators are working or not. Is there a budget tool that will do this?

Also, is there a write up/video on accessing and changing the actuators? I've seen them on the older trucks, but can't find anything on the 15+

Any information is appreciated.

 

[Joseph Garcia]

Sounds like a blend door actuator issue. @swathdiver is pretty familiar with these parts, and he may be able to provide some perspective.

I recommend that you get yourself a quality bi-directional scanner to add to your tool box. Then, you will be able to read ALL trouble codes, along with a brief explanation/pointer to the source of your issue. You will also be able to reset/delete trouble codes, after taking corrective action. You will literally save thousands of dollars in diagnostic and repair costs over the life of your truck, and you will most likely recoup the cost of the scanner within 1 year.

With a quality bi-directional scanner, you could test each of the blend door actuators and reset their opening and closing positions. Autel makes a good quality bi-directional scanner.

 

[swathdiver]

2017 Denali XL - 110k miles
Rear A/C is still ice cold, front A/C is room temp/ambient.

I have searched a handful of times and keep coming up with the same results. Sounds like I have a blend door issue.

What diagnostic tool can I purchase to diagnose this myself? I know some tools will actuate each blend door on command to verify if the actuators are working or not. Is there a budget tool that will do this?

Also, is there a write up/video on accessing and changing the actuators? I've seen them on the older trucks, but can't find anything on the 15+

Any information is appreciated.

You need a bi-directional scan tool. I use a GM MDI and a laptop with a subscription to GMs GDS, very expensive. We used a TOPDON a couple weeks ago that worked fine on several cars including a GM vehicle like yours.