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A/C switches off over night

ChrisVincent

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Hi all, been lurking for a while and learning, shame I need to post because of an issue. I purchased a new S650 6 months ago and love it, first Mustang, first American car and enjoying it much more than the AMG‘s etc owned before, amazing machine! Car has done all its updates and an issue came about after the last update, A/C switches off if locked and parked over night, probably after an its deep sleep. All functions work, fan, heater etc but the A/C switches off, I have to press the button on the screen each day to make it work, being in the UK it needs it otherwise the windows steam up. If I press the max button it comes on, if I set the temp to below 21 it comes on, temp set to 24 and I have to manually put it on. Been back to dealer twice so far, software check, modules reset but still the same, I have also done the screen reset and battery disconnect overnight still no joy, don’t get me wrong I don’t mind turning it on but all cars I have owned have not done this. Anyone experienced, is it normal or can someone look on forscan to see if there is a setting incorrect? Cheers, Chris.
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A.alansari

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Not sure if you tried this but there is auto ac settings somewhere in the menu check and see if its on turn it off
 
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ChrisVincent

ChrisVincent

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Thanks for the suggestion, would love to find that, i thought I had looked in all the menus I could find, i will have another look tomorrow do you have an idea where I may find it?
 
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AZ_Ryan

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The climate control settings dont save over night. Its not a glitch, that's just not how the car works. Try setting the climate settings to auto when using remote start, it will run the AC or heat depending on ambient temperature. Once in the car use the auto feature for climate after its started. Its pretty easy.
 
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ChrisVincent

ChrisVincent

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The climate control settings dont save over night. Its not a glitch, that's just not how the car works. Try setting the climate settings to auto when using remote start, it will run the AC or heat depending on ambient temperature. Once in the car use the auto feature for climate after its started. Its pretty easy.
Thank you for the reply, ok that’s interesting, when I first got it before any updates it was always on, but it was summer of course and a lot hotter, I did try the auto a few times last week and the car fogged up so I quickly switched the AC on Manually, so may not have waited long enough, mind you I would not be able to see if left any longer, it could be that because it lives in a heated garage it does not have time to adjust to the cold outside humidity and temperature? It is a tad annoying have to put it on each day, another button to press with turning off all the stuff I don’t want, the start stop, lane control etc 😁 if it is correct as you say I would be happy and chock it down as a feature 👍 thanks.
 

Gregs24

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Use the 'auto' setting and it will sort itself out when it needs to. I pressed 'auto' on day 1, set the temperature and have never touched the HVAC system controls since.

Note: The AC will NOT come on below an external temperature of 4C whatever you do, to avoid damage to the system.

S650 Mustang A/C switches off over night 1766332244236-23
 

davidsteele1975

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I'm a little late to the thread but I've noticed mine does a similar thing. The car is more decisive if she wants to use or not use the compressor. Sometimes, I'll be driving to work and the A/C has turned on or turned off, depending on the outside temperature. I keep mine in a (typical American, so not as well insulated as the British ones) garage, which can be warmer or cooler than outside, so sometimes when I start the car in the morning with the system in Auto, it'll enable or disable the A/C only to change its mind later.

You can use Auto, and the Ford voice control might let us turn it on or off with a voice, if we Brits add a "yeehaw" in there somewhere so it understands our accent. :wink:
 
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ChrisVincent

ChrisVincent

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I'm a little late to the thread but I've noticed mine does a similar thing. The car is more decisive if she wants to use or not use the compressor. Sometimes, I'll be driving to work and the A/C has turned on or turned off, depending on the outside temperature. I keep mine in a (typical American, so not as well insulated as the British ones) garage, which can be warmer or cooler than outside, so sometimes when I start the car in the morning with the system in Auto, it'll enable or disable the A/C only to change its mind later.

You can use Auto, and the Ford voice control might let us turn it on or off with a voice, if we Brits add a "yeehaw" in there somewhere so it understands our accent. :wink:
lol excellent, appreciate the heads up so it sounds like all is normal, which I am well pleased about, I use alexa, nice british lady voice that seems to do nearly everything I ask for, unlike the missus 😁
 
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ChrisVincent

ChrisVincent

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Use the 'auto' setting and it will sort itself out when it needs to. I pressed 'auto' on day 1, set the temperature and have never touched the HVAC system controls since.

Note: The AC will NOT come on below an external temperature of 4C whatever you do, to avoid damage to the system.

1766332244236-23.webp
thank you, not had much below 4 yet but it looks like ithe system is all normal, I will put it on auto and see if I see it come on after a little time out of the garage. Thanks again.
 

davidsteele1975

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TL;DR - I think it tries to be smart but either needs better calibration or a humidity sensor, or both,

It's been interesting to watch how mine behaves - the a/c feels like it overcools on a warm day, like "arctic blast" overcools, but when it's warm but not hot, if I tell the system to cool the interior compared with ambient air temperature it'll use the a/c. It will also use the a/c if I'm say asking the car interior to be 72F (22C) and it's 63F (17C) outside, and it's sunny, or the interior is warm.

It tries to be smart, I think; in my 2020 Fusion (nearly a Mondeo) when I told the system to use the a/c, it would use it unless it was bloody cold outside. If I shut it down on a hot day it would shut it down, and run the fans harder to compensate.

I hear you on needing the a/c to demist the interior - and that's somewhere that the system isn't as great for me. Sometimes the temperature varies a lot on my commute, like it'll move from 50F (10C) to 60F (16C) with and without mist on the morning commute. It struggles to demist the windscreen even with heat, unless I use the a/c, but when the temperature drops it'll sometimes shut the a/c down and immediately start to mist up.

All of my other Fords have had great systems, but the Mustang's ventilation and heater system is merely... okay. I appreciate it wants to shut down the compressor if it's cold outside but I feel this decision should also rely on a humidity sensor, as cooling temperatures and rising relative humidity means condensation so either boost the heat more or run the compressor.

And YES I get it. Driving a Mustang and watching the ambient air temperature and how the car behaves is probably missing the point of the Mustang.

LASTLY how's the Mustang in the UK? I emigrated almost a decade ago and was never in a position to buy a Mustang over in Blighty, but now in the US, they're relatively way more affordable and fairly small. The Mustang's enormous doors and wide stance would have felt a liability in York.
 
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ChrisVincent

ChrisVincent

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TL;DR - I think it tries to be smart but either needs better calibration or a humidity sensor, or both,

It's been interesting to watch how mine behaves - the a/c feels like it overcools on a warm day, like "arctic blast" overcools, but when it's warm but not hot, if I tell the system to cool the interior compared with ambient air temperature it'll use the a/c. It will also use the a/c if I'm say asking the car interior to be 72F (22C) and it's 63F (17C) outside, and it's sunny, or the interior is warm.

It tries to be smart, I think; in my 2020 Fusion (nearly a Mondeo) when I told the system to use the a/c, it would use it unless it was bloody cold outside. If I shut it down on a hot day it would shut it down, and run the fans harder to compensate.

I hear you on needing the a/c to demist the interior - and that's somewhere that the system isn't as great for me. Sometimes the temperature varies a lot on my commute, like it'll move from 50F (10C) to 60F (16C) with and without mist on the morning commute. It struggles to demist the windscreen even with heat, unless I use the a/c, but when the temperature drops it'll sometimes shut the a/c down and immediately start to mist up.

All of my other Fords have had great systems, but the Mustang's ventilation and heater system is merely... okay. I appreciate it wants to shut down the compressor if it's cold outside but I feel this decision should also rely on a humidity sensor, as cooling temperatures and rising relative humidity means condensation so either boost the heat more or run the compressor.

And YES I get it. Driving a Mustang and watching the ambient air temperature and how the car behaves is probably missing the point of the Mustang.

LASTLY how's the Mustang in the UK? I emigrated almost a decade ago and was never in a position to buy a Mustang over in Blighty, but now in the US, they're relatively way more affordable and fairly small. The Mustang's enormous doors and wide stance would have felt a liability in York.
Hi David, thanks for the reply I have come to the conclusion it’s normal, dealer has been over it twice and reset the systems to no avail, they want it back in the new year as the claim is still open, loathed to give over again. I must say Ford UK have been great all the way but would have preferred a better courtesy car than a puma but can’t complain, if they said it’s normal I would have been happy and walked away with the knowledge. Owning a Mustang over here, a new one at that, that I daily commute has been a learning curve, I have always had fast cars last one was an A35 AMG but the Mustang is an event ever time I use it, love that engine. It’s better built that the Merc and customer service is miles better. Unless we are going somewhere that is a, not a public small car park, b, not awkward to drive like small country lanes I find it great to drive around now I’m used to the bonnet, we have the wifes VW GTI for the nasty stuff. It is fine for the southeast where I live, no bigger than a 5 series Beemer I suppose. My friend has a 2018 for fun days and says the convertible is much easier to navigate as the side windows have the smallest pillar and his coupe is quite restrictive to judge parking etc. I do wish it had front parking aids though, I am very careful. 👍👍
 

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Hi David, thanks for the reply I have come to the conclusion it’s normal, dealer has been over it twice and reset the systems to no avail, they want it back in the new year as the claim is still open, loathed to give over again. I must say Ford UK have been great all the way but would have preferred a better courtesy car than a puma but can’t complain, if they said it’s normal I would have been happy and walked away with the knowledge. Owning a Mustang over here, a new one at that, that I daily commute has been a learning curve, I have always had fast cars last one was an A35 AMG but the Mustang is an event ever time I use it, love that engine. It’s better built that the Merc and customer service is miles better. Unless we are going somewhere that is a, not a public small car park, b, not awkward to drive like small country lanes I find it great to drive around now I’m used to the bonnet, we have the wifes VW GTI for the nasty stuff. It is fine for the southeast where I live, no bigger than a 5 series Beemer I suppose. My friend has a 2018 for fun days and says the convertible is much easier to navigate as the side windows have the smallest pillar and his coupe is quite restrictive to judge parking etc. I do wish it had front parking aids though, I am very careful. 👍👍
An aftermarket sensor system or front cam is worth it's weight in splitters. I've got both on mine
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