Auto Temp Control problem

[Vicompc]

My Auto Temp Control will not switch to Max A/C, I have reset the head unit and it does not help. Any ideas on how to fix this problem?

 

[The_Roadie]

Do you mean the control module ignores it when you press the button, or the recirculate actuator doesn't move to change the airflow? The recirculate actuator is the worst to access, and does involve a lot of dash disassembly.

 

[Vicompc]

I apologize for the confusion. I thought the auto ac was supposed to automatically switch to max based on the temperature. The manual button and actuator appear to be working correctly.

 

[The_Roadie]

It sort-of auto switches to max for me if the cabin temp is really hot. But the cabin temp sensor data is not accessible without a Tech II tool. You might have an issue with that sensor in the B-pillar next to the driver's left ear. You might pull the pillar cover and make sure the tiny squirrel cage fan is spinning, or if it's clogged up with spiderwebs.

I think even if it auto-engages the recirculate mode, the display on the control module doesn't say so. Even when it's on auto-max, the blower still isn't on the absolute highest speed, and you can override that manually.

What I miss that I heard the Escalades and possibly Tahoes have is auto-blower-speed-reduction whan a hands-free call came in on the Verizon/On-Star interface. Now the Roadiemobile is no longer a DD, I gave that cell line up to save $10 a month, and just use a separate Bluetooth speakerphone.

 

[Denali n DOO]

I apologize for the confusion. I thought the auto ac was supposed to automatically switch to max based on the temperature. The manual button and actuator appear to be working correctly.

In auto mode "max a/c" is achieved by setting temp setting to the coldest postion. Raise the temp setting by 1deg and it goes back to normal auto mode.

 

[The_Roadie]

Seven years living and breathing GMT360s and I never knew that. Slap me silly. (I actually never tried that because, as the manual says, it doesn't really make the AC work any harder, but it does force it into recirculate mode.)

I knew item #1, but don't remember reading the second entry in the manual. Good eyes!

View attachment 22029

 

[Vicompc]

Thanks I'll try the 60 degree trick and if that doesn't work I'll look at the sensor