Air conditioning is always turning itself back on when starting, even in manual HVAC mode

[Bonehead]

Call me crazy, but when it's cold out I don't like to have the AC on.

When starting the car up, most settings are retained from your last drive. But if you have the AC off when you turn the car off, for some reason it seems impossible to not have the damn AC turn itself on every time I start. It wouldn't be so bad if there was a physical button to turn it off or at least if you could turn it off with a voice command (you can't), but it's a nuisance to do it via 3 button presses on the screen every time I start up in the winter (I know, I know, first world problems).

And it's not an issue of it turning on because it's humid, which it isn't.

My first thought was that this would only occur when one of the 3 Auto settings was on, and for a while it seemed that using manual instead with a low fan speed and E-Heat on fixed the problem.

No more for some reason - even in manual, the AC is now always on when I start. Anyone else have the same issue?

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[srogers]

Yes, it happens in my car too. I reported it to the dealer, but they were unable to reproduce the issue. The e-heat comes on, too even though I had previously switched it off.

 

[Murse-In-Airy]

You’re just going to have to let it go. The A/C button may be on, but the A/C compressor isn’t actually running unless the car is trying to cool. It not doing anything to the car.

 

[srogers]

You’re just going to have to let it go. The A/C button may be on, but the A/C compressor isn’t actually running unless the car is trying to cool. It not doing anything to the car.

Yes, the compressor runs. I can feel the cold air and hear the compressor running.

 

[Bonehead]

You’re just going to have to let it go. The A/C button may be on, but the A/C compressor isn’t actually running unless the car is trying to cool. It not doing anything to the car.

It's not just the button - I feel the cold air blowing, and it's freezing out.

 

[Maquis]

Yes, it happens. Just today, it was 64 outside, I had the temp set to 68 and the fan on auto. Next thing I know, it’s freezing cold in the car. Checked the HVAC controls and AC is on. The AC, E-Heat, and recirc settings all have a mind of their own.

 

[Carsinmyblood]

It's to control humidity inside the car. If it's cold outside the windows will fog. My mom's old VW Beetle always had a roll of paper towels on the front seat.

My Mazda CX5 did the same thing.

 

[srogers]

It's to control humidity inside the car. If it's cold outside the windows will fog. My mom's old VW Beetle always had a roll of paper towels on the front seat.

My Mazda CX5 did the same thing.

As the originator of this post stated "And it's not an issue of it turning on because it's humid, which it isn't."

I live in an area where the weather is mild and I don't use the A/C or heat much. I had a 2013 Fusion and it initially had the same issue with the A/C turning on when it wasn't needed. Eventually, Ford came up with a software patch that fixed the problem.

 

[Mach1E]

As the originator of this post stated "And it's not an issue of it turning on because it's humid, which it isn't."

I live in an area where the weather is mild and I don't use the A/C or heat much. I had a 2013 Fusion and it initially had the same issue with the A/C turning on when it wasn't needed. Eventually, Ford came up with a software patch that fixed the problem.

Does the car even have a humidity sensor? I think the car just makes assumptions.

I have the opposite problem in Florida. Car won’t leave recirculate on to prevent fogging/humidity.

The problem is that the outside air is waaaaaay more humid than inside when the a/c is on.

 

[srogers]

Does the car even have a humidity sensor? I think the car just makes assumptions.

I have the opposite problem in Florida. Car won’t leave recirculate on to prevent fogging/humidity.

The problem is that the outside air is waaaaaay more humid than inside when the a/c is on.

Yes, the Mach E has a humidity sensor to the left of the rearview mirror.

 

[Mach1E]

Yes, the Mach E has a humidity sensor to the left of the rearview mirror.

Maybe the better question then will be: what does the humidity sensor do?

 

[Maquis]

Maybe the better question then will be: what does the humidity sensor do?

It turns on the AC and freezes your ass off, that’s what it does. ?

 

[Studly]

Does the car even have a humidity sensor? I think the car just makes assumptions.

I have the opposite problem in Florida. Car won’t leave recirculate on to prevent fogging/humidity.

The problem is that the outside air is waaaaaay more humid than inside when the a/c is on.

Recirc is 99% the reason for fogged windows, even when it's humid outside. Outside air with compressor is the best option to no fog. Recirc on with people inside and breathing raises humidity quickly.

 

[KevinS]

I've quit trying to second-guess the climate controls on the MME and my sanity has improved.

 

[Carsinmyblood]

I've quit trying to second-guess the climate controls on the MME and my sanity has improved.

I gave up in 1994 with my 3rd Chrysler minivan.

How I WISHED I had A/C in my '66 E-Type on one certain day last year. I hit an area of fog on the way home from a car show and even with the windows open (top up) the inside of the windshield went white with condensation.

That will happen in any car where the glass is cool and there's humidity in the air. A/C dries the air acting like a de-humidifier.... even if the heater is on too.

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