2007 Mazda 3 touring vent question

[Ryland]

I have the manual climate control system in my M3 and found that if I turn the knob to Defrost then back to Vent (at face level) the AC and Recirc lights come on when I had the AC off when I was on Vent to start with. Does this happen to anybody else?

 

[Gibson486]

yes....it happens on all 3's.

 

[Ryland]

I wonder if they assume that since you turned it to Defrost that the inside of the car is humid and needs to be dried...
I killed my mileage this tank by leaving it on foot venting because I didn't realize that turns the AC on.

 

[Gibson486]

killing gas mileage in a 3 is not hard, unfortunately.

 

[Riverhound777]

yup, happens on them all. In fact I believe if you have the knob anywhere to the right it turns on the ac. I always keep mine to the left of center unless it fogs up.

Quote from mazda3forums for more clarification on the AC thing:

"hey this might be news to some of you as it was to me but anyways here it is. The ac pump on the 3 is not turned on only buy the ac button. The ac pump will be on if either of 2 conditions are satisfied: the ac button is on, OR you have the vent controls set on either the foot setting (pointing up) or point on any of the settings to the right of that. The only way to have your ac pump off (and get the extra power as well as the extra mpg) is to have the air coming set on one of the leftward facing settings. (face, face/feet)

you can actually hear the pump turn on as you switch to the feet only mode."

 

[jagec]

Mazda 3 != M3, sorry.

I hate that the AC turns on automatically on newer cars. My old VW had the whole "if defrost, then AC" thing, so I installed a switch. I control the AC compressor, not the car.

 

[ggnl]

Every newer car I've driven has done this, not just the 3.

 

[Ryland]

Thanks for the info on the knob being up and to the right turning the ac on. I don't mind the AC coming on when I am on defrost but that is all it should automatically do.

 

[Jawo]

Thats good to know since I just got a Mazda6.