I have a 64 Fiesta Zetec S red edition with the EATC (Electronic Automatic Temperature Control) option.

Just wondered if having this option means that I can leave the AC button on all the time, therefore meaning the car will only then use the AC when it needs to to reduce the air temperature.

If you leave it on Auto all the time, then the EATC will turn A/C on as it is needed.

Does this apply to 2011 Fiestas with EATC too, like my Titanium? Am sure in mine when the aircon button is on, then AC is on continually. It doesn't show Auto like the left button does.

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My 2013 facelift is always on in auto mode unless I turn it off.

I leave the control on left on auto but manually work the aircon side

On auto, although the ac light may on, it just means it can turn it on and off as it needed.

It won't be running all the time

Does that mean that it only runs when it's needed?

For example, if I have it on and I accelerate hard will it be switched off to divert power to the engine instead?

This is exactly how the climate control system Works. You have 3 options usually 1 eco aircon off 2 AC aircon always on manual control 3 auto aircon always on auto control of heater vents, airflow and temp. What you have to way up is it worth not being in auto and loosing ac all together. AC these days does cause the car to drink fuel like it used too. I've found it only effects mpg by .1 - .2 which is nothing really. The benefits of being in auto are quite big I've found as ac removes moisture from the cabin no more foggy windows, just set the temp and it will do the rest for u and it keeps ur concentration more on the road. I never have it off in my ST plus if you don't use the AC on a regular basis it will damage the system which then becomes very expensive to repair. I've seen endless cars having AC fixed because it's not been used all winter. If u use it regularly most systems only ever need to be serviced and gassed every 24months

Sorry!!! AC THESE DAYS DOES NOT CAUSE THE CAR TO DRINK FUEL LIKE IT USED TOO.

How come the AC fan (engine bay) is always on then? I'm sure AC is always on on my 2011 when AC (switch) is on. I don't understand what you mean by the three aircon settings tho...surely it's either on or off? I'm obviously missing something :)

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It's only the climate control aircon that has 3 settings. I'm not sure what there called on fords but on my old seat it had auto which is aircon on in auto mode. Example you set the temp at 18c and that's it fan speed and vents controlled by computer so the car stays at 18c or there abouts. AC This is when u set the fan speed and which vents yourself. For example fan speed 2 windscreen and floor vent setting. Then the old fashioned mode eco which is no AC and fan speed and vents set by you.

I getya thanks :)

So I can assume that when the AC button is on, the AC is always running and not just when needed.

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I getya thanks :)

So I can assume that when the AC button is on, the AC is always running and not just when needed.

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LOL i just get in and turn it on myself,way above my head as i did think when auto light is on the aircon is on so

if too hot it kicks in to cool it when you set to a temp.

Yep that's correct if the AC light is on the AC is on. It is more beneficial to just leave it on auto than not really. As the saying goes in the motor trade with aircon IF U DONT USE IT U WILL LOSE IT. As not using it for long periods damages the AC system.

What happens when you press auto then press ac button off then? My autofan still works but doesn't use ac

Yes that's correct the fan speed and vents will still b automatically controlled but the AC will be off and it will just work the old fashioned way.

See a asked this because this is what I use it for only use ac if it's very warm to cool car down or very cold to heat car up lol