Dash vent temp when in auto?

[cparker]

Seems like sometimes my dash vents change temperature while the hvac is in "auto" and sometimes they are just whetever the little selector dial is set at.

Am I dillusional? Right now they are only responding to changes on the temperature selector dial on the middle dash vents and not changing temps with the other vents.

Anyone else experience this?

[Mtnman]

Do they change temp if you manually make them come on? keep the temp on auto, but hit the button for the air to just come out of those vents and adjust them and see what happens.

[zj96sc]

Pretty certain the center vent temperature is controlled solely by the selector dial. Keep in mind that as your car warms up the "hot" will get "hotter" as coolant comes up to temp.

[edlvrt]

The way I understand it: The temp selector dial on the dash controls whether air feeding the face level vents passes through the heater core or not. When it is set to three blue, air bypasses the core, and passes through when set to red. That's why you can have the digital control set at 90 and the dash control on three blue dots, and the air out of the dash will be cool.

If you have the dash set to three red dots, than all the air passes through the heater core. With that, the temp of the air will correlate to how you have the digital controls set. When the dial is set somewhere in the middle, you get a mix depending on where you set it.

With that in mind, it is possible that the air is coming out at different temps as the auto setting tries to get the cabin to the temp set by the digital controls. Once at that temp, the auto function will warm or cool the air coming out of the vents as necessary to main that temp.

[cparker]

Thanks guys. I'll try to set it all the way warm and see if it changes temp.

If I set it on auto and select dash vents only it changes temperature based on the automatic settings.