[stylett9]

So i just purchased a 2004 used Mazda6S

great car, love it but i cant seem to understand when the AC is on, and when its not.


so whenever i set the fan to run up on the window and down on the feet, regardless of what temperature i set the fan to, i hear a noise from my engine bay*the kind of noise you hear when your AC turns on* but the AC light is not on. So does this mean my AC for sure is NOT on, or is it one of those things where your car assumes your trying to defog the window so it automatically turns the AC on? i like to leave my fan running all the time on a low setting up on my window and down on my feet so that there is some air circulation in the car without having to roll down the windows but if its turning the AC on then i guess i dont want to do that anymore.

i guess what i really want to know is when does the ac come on and when does it not.
thanks in advance

 

[Mazda Gremlyn]

When you are using the auto climate control, IIRC the AC is always on, just not always used. If you manually control temp then it is on or off depending on the setting.

 

[stylett9]

When you are using the auto climate control, IIRC the AC is always on, just not always used. If you manually control temp then it is on or off depending on the setting.
[/b]

if it IS on, will the AC light turn on? cause i notice that when i defog my windows it will defog them really quickly and i thought that was wierd cause in my accord, to get the windows to defog i HAD to use AC.

 

[Mazda Gremlyn]

My memory says no, the light isn't always on when the system is.

 

[Vault172]

If you use the auto setting you can turn the AC off but the "auto" will still control the fan speed. If you adjust the fan speed you will "turn off" the auto control. From what I've read the AC isn't ON unless the light is on.

I agree with stylett9 in always having the fan on for some circulation. Just hit auto, adjust the temp, then hit the AC button to turn off the compressor. To adjust the fan speed just change the temp, not the fan knob and you'll be fine.

 

[stylett9]

If you use the auto setting you can turn the AC off but the "auto" will still control the fan speed. If you adjust the fan speed you will "turn off" the auto control. From what I've read the AC isn't ON unless the light is on.

I agree with stylett9 in always having the fan on for some circulation. Just hit auto, adjust the temp, then hit the AC button to turn off the compressor. To adjust the fan speed just change the temp, not the fan knob and you'll be fine.
[/b]

good idea, never thought about doing that. but yeah its kind of frustrating that there doesnt seem to be a way to just keep the fan going without AC. ohwell, still love the car

 

[nashirak]

The compressor DOES cycle on when you either

A) use the auto control

or

B) put the vent to either defrost, feet, or any combination that involves either feet or defrost.

It's annoying to me so I just use the dash vents just because I don't want the fuel burned to spin the compressor; unless I NEED to defrost my windshield, and even then I turn it back to the dash ASAP.

 

[Koya]

Its strange to worry about ac because of fuel

 

[JTZako]

In most modern cars (including the 6s) the A/C causes less than 2% difference in fuel economy.. so "going without" isnt really helping you save much.

The A/C does cause a fairly significant reduction in acceleration though so I usually dont run it unless its hot enough that just having the windows open isnt enough. I have yet to even turn on the heater in my 6s either.

 

[Kansasdog]

^^^^^^^^^^^^^^^^^^^^^^

So how is the weather in Hawaii?

Looking out my office window at a 39 degree rainstorm.

 

[JTZako]

Dunno about Hawaii but here in Dallas one day its nice and in the 70s.. the next day its around 40 and raining... I actually turned on the defogger last night so I could see... but I still refuse to use the heater if its above freezing outside. I guess Im just tolerant of cold though.

 

[nashirak]

In most modern cars (including the 6s) the A/C causes less than 2% difference in fuel economy.. so "going without" isnt really helping you save much.

The A/C does cause a fairly significant reduction in acceleration though so I usually dont run it unless its hot enough that just having the windows open isnt enough. I have yet to even turn on the heater in my 6s either.
[/b]

Mine mileage is a noticeable difference. During the summer I use AC because I have to (sweating through clothes is just not cool). I usually get on average about 2mpg less in a tank where the AC is used a lot versus not using the AC at all. It adds up on a budget.

I understand the Dallas weather. Today it's sunny and mid 60's. A couple weekends ago it was highs in the high 30's low 40's. Winter in Georgia will drive you nuts with the fluctuations. You'll freeze your ass off in the mornings going to work then be sweating in all the extra clothes you brought with you.

 

[LapisLazuli6]

My memory says no, the light isn't always on when the system is.
[/b]

Even on the manual climate system, the AC is always on if you're in defrost or mix (windshield/feet) mode,. but the light won't be on. You can hear the AC compressor cycle off and on though.

With the auto system, it may also cycle the AC compressor off and on to maintain your temperature in something called 'econ' mode (the compressor runs sometimes, not fully like full AC mode).

Hope this helps, and congrats on the new car purchase. Post some pics!

 

[KevinK2]

The compressor DOES cycle on when you either

A) use the auto control

or

B) put the vent to either defrost, feet, or any combination that involves either feet or defrost.

It's annoying to me so I just use the dash vents just because I don't want the fuel burned to spin the compressor; unless I NEED to defrost my windshield, and even then I turn it back to the dash ASAP.
[/b]

Based on my 04 with ACC:

If you have ACC and are selecting modes, you can only stop compressor in DASH or DASH + FEET modes .... AC light goes off.

Note that while flipping through modes, if AC lite is off for a mode, that means it will be used as needed and you can not turn it off while flipping modes.

In cold weather, ACC starts in DEFROST + FEET mode, and migrates to FEET mode (which still includes some defrost flow), and AC is used. IF you want this combo with no AC, you must turn on ACC (ac lites up) and then turn off AC button (ac lite off). The compressor will stay off, day after day, as long as you do not touch the mode switch.

 

[bitslizer]

Mine mileage is a noticeable difference. During the summer I use AC because I have to (sweating through clothes is just not cool). I usually get on average about 2mpg less in a tank where the AC is used a lot versus not using the AC at all. It adds up on a budget.

I understand the Dallas weather. Today it's sunny and mid 60's. A couple weekends ago it was highs in the high 30's low 40's. Winter in Georgia will drive you nuts with the fluctuations. You'll freeze your ass off in the mornings going to work then be sweating in all the extra clothes you brought with you.[/b]

+1 on 2mpg diff

I typically get 21-22mpg per tank on the v6, with about 270miles when the tank reach the 1/4 tank remaining mark.

the MPG is pretty consistent during summer and winter too.... I expected now it is winter(chicago) that the Mpg should go up because the compressor should run less, but no

I turn the auto climate control off this tank and now I'm at 310miles at the same mark. which is about 2mpg so far. I will know the exact difference once I refill and do the mpg calculation