which HVAC actuator? (2011 Tahoe)

[GordoPanocho]

***Assuming an actuator is the issue, any idea which one is my problem?***

According to one search, the most common culprits for an AC not blowing cold are low refrigerant, a faulty A/C compressor relay, a bad evaporator temperature sensor, or a clogged condenser. But the rest of my searches keep pointing to actuators.

I've searched a lot of sites and watched various YouTube videos, but I often second guess myself. So, here's what info I've collected.

2011 Tahoe LTZ
dual zone electric climate control
* My AC isn't blowing cold. It just blows harder the closer I get down to 60°. Nothing makes it blow colder.
* When I leave the driver side at 60° and take the passenger side to 90°, all upper (dashboard) vents barely blow.
* When I do the reverse (driver 90°, passenger 60°), it quits putting out air in the upper vents and kicks in the heat/defrost vents; I can hear and feel it.

I completed the HVAC reset/recalibration by pulling the fuse(s) etc. It did start back at 74° as it should but it didn't fix my issue. I didn't think it would anyway.

I keep seeing three (3) main actuators in the "how to repair" videos. They were described as follows:
* driver side (behind/under steering wheel) -- mode door actuator (air direct)
* passenger side (near feet) -- driver side blend door actuator (temperature)
* passenger side (behind upper vents) -- passenger side blend door actuator (temperature)

I hope to get it scanned soon in case I can clear the Diagnostic Trouble Codes (DTCs) and perhaps find one of the following (assuming they're correct):

* B0228 recirculate actuator
* B0413 drivers air temperature actuator
* B0423 passenger air temperature actuator
* B0433 auxiliary air temperature actuator
* B3779 mode actuator
* B3782 auxiliary mode actuator

And I came across this list of part # info:

* 89018365 Air Inlet Valve Actuator Behind Glove Box Above Blower Motor Installed Vertically and Facing Left Side
* 89018374 Mode Valve Actuator Behind Navigation Left of Center Vents Installed Vertically and Facing Left Side
* 89018375 Temperature Valve Actuator - Driver's Side Passenger Footwell Towards Console Installed On Bottom and Facing Down
* 89018375 Temperature Valve Actuator - Passenger Side Behind Navigations Right of Center Vents Installed Horizontally On Top

 

[Joseph Garcia]

@915_Tahoe may be able to help you confirm correct part numbers, if you post the last 8 digits of your VIN.

 

[Fless]

You may need to have professional A/C service done, at least to verify that the system is fully charged and cooling properly.

And a capable bidirectional scanner will show you all the actuators with their commanded positions vs. actual positions. That would save you some grief if it tells that they're working correctly, or to pinpoint the cause.

 

[swathdiver]

2011 Tahoe LTZ
dual zone electric climate control
* My AC isn't blowing cold. It just blows harder the closer I get down to 60°. Nothing makes it blow colder.
* When I leave the driver side at 60° and take the passenger side to 90°, all upper (dashboard) vents barely blow.
* When I do the reverse (driver 90°, passenger 60°), it quits putting out air in the upper vents and kicks in the heat/defrost vents; I can hear and feel it.

Does the AC blow cold at all out of any of the vents?

 

[intheburbs]

If it's not blowing cold at all, start with the basics. When you press the A/C button, does the LED light up and stay on?

Next:
1) Is the compressor turning? Is the belt tight? The A/C has a separate belt, it doesn't run off the serpentine.
2) Is the system charged and pressurized? Are your high/low sides in spec?

Once you're sure you're getting cold in the evaporator core, then you can start troubleshooting interior things like blend doors. But I'll bet $1 you're low/out of freon, or your compressor died.