A/C Always on in Defog!

[PBH]

Hey guys! I'm new to the forum theing, so excuse me if this has already been addressed.

It seems that the AC is constantly on when I have the selector dial in defog status, even when the temperature dial is set to hot!

Is this normal?:wtf:

 

[Kooldino]

You did try pushing the AC button to turn it off, right?

 

[20ESGUY]

Yep its normal....in most modern vehicles the A/C will run when in defrost mode no matter what the temp selector is set at. If you don't want the A/C to run you can only avoid it by not turning on the fan, if you set the fan speed to 0 it won't turn on.

 

[njaremka]

yeah, most new cars come stardard with that feature because the air conditioner will dry out the air that it blows throught he system. (one of the thing an air conditioner does) the only way to by pass it, and still have the fan on, is to take apart your dash and disable the switch that kick the ac in when you turn the knob past the 'floor' setting.

 

[Jim Frye]

The Logic Behind This...

is that the AC will remove the moisture from the incoming air, the heater will warm the dry air and make defogging or defrosting quicker and more efficient. GM cars have been this way for decades. Jim

 

[Todd]

I have a question. When I put the fan setting to 0 I still get some hot air or cold air regardless, I assumed that 0 would mean the thing is off. Is this working as designed or is mine broken???

 

[njaremka]

if your car is moving, there will always be air flow through the vents.

 

[20ESGUY]

Yeah, what NJ said is correct....if you notice the little black bar at the bottom of the HVAC panel when you turn to defog it automaticly changes to fresh-air mode (green light) you have to take it off of the defog mode to return to recirc mode (red light)

 

[Todd]

if your car is moving, there will always be air flow through the vents.

Thanks!! Thats all I needed to know.

 

[PBH]

Thanks for the responses guys. I'm obviously in the right club. I wish you guys all the best with your vehicles & thanks again.

 

[BigBlue]

I have a question. When I put the fan setting to 0 I still get some hot air or cold air regardless, I assumed that 0 would mean the thing is off. Is this working as designed or is mine broken???

Yup you do...I just put mine on full defrost when the fan is on 0....the air is still there, I just don't really notice it.

 

[mp5]

the only way to by pass it, and still have the fan on, is to take apart your dash and disable the switch that kick the ac in when you turn the knob past the 'floor' setting.

how difficult is this, can you get to the swich just by pulling the radio, what does the switch look like/color of wires etc?

I don't mind the a/c coming on in deforst, but I hate that it kicks on and doesn't allow you to recirculate the air in floor mode.

 

[njaremka]

i don't know. maybe someone with a wiring diagram can help out.