[Oz M5]

Hi all

Recently in to a 2019 M5 Comp., and loving every bit of her... well apart from the HK sound system but that's not just me! 😉

Anyway, having an issue with the a/c not being cold. Just started a few days ago and was fine before that.

If I select 16degC (coldest temp) and select 'auto', even with the fan at the max setting, the fan minimally blows.... and this is on a 40degC day in Houston just after jumping in the car as she's sat in the midday sun.... that is, she's a lot hotter than 16deg inside! The rear climate does exactly the same.

When I press Max a/c she just blows air that feels slightly below ambient.

I've also noticed that 'seat ventilation', which I had set to automatically activate when Temps were above 25degC, no longer automatically activates.

It's as if the cabin temp sensor thinks the car is below 16deg.

I've checked the a/c gas pressure and it's ok at 31 psi but this seems to be more a sensor issue.

I did install a Racechip Black last week, but wouldn't think that would have any issue with the HVAC system.

Any ideas as I'm dying here in Houston without a/c.

Thanks

[AHall]

Originally Posted by Oz M5

Hi all

Recently in to a 2019 M5 Comp., and loving every bit of her... well apart from the HK sound system but that's not just me! 😉

Anyway, having an issue with the a/c not being cold. Just started a few days ago and was fine before that.

If I select 16degC (coldest temp) and select 'auto', even with the fan at the max setting, the fan minimally blows.... and this is on a 40degC day in Houston just after jumping in the car as she's sat in the midday sun.... that is, she's a lot hotter than 16deg inside! The rear climate does exactly the same.

When I press Max a/c she just blows air that feels slightly below ambient.

I've also noticed that 'seat ventilation', which I had set to automatically activate when Temps were above 25degC, no longer automatically activates.

It's as if the cabin temp sensor thinks the car is below 16deg.

I've checked the a/c gas pressure and it's ok at 31 psi but this seems to be more a sensor issue.

I did install a Racechip Black last week, but wouldn't think that would have any issue with the HVAC system.

Any ideas as I'm dying here in Houston without a/c.

Thanks

Are you saying if auto is turned off and max AC is on you do not feel maximum air output and the air temperature is not cold?

I would say the system is defective and I would take the car in for service.

[Oz M5]

First, thanks for chiming in. Much appreciated.

No... When I press 'max-a/c' the blower goes to full power but the air only feels slightly colder than ambient.

My main concern is that when I press the auto button and the fan speed is set to high, even with the temp set to its lowest setting (16degC) and the cabin of the car feeling like it's over 38degC (100+F) the 'auto fan' blows minimally, as if the car thinks it's close to 16degC therefore doesn't need to work hard to lower the cabin temp.

If I then disable auto fan, I can manually increase the blower speed but like max a/c it blows air slightly colder than ambient.

The seat-blower is set to come on automatically for Temps above 25degC, however it's not coming on automatically. Again, points to a sensor issue.

All was working fine a week ago. I think she's just had enough of this brutal Houston weather!

Looks like I'll need to take her in for a diagnosis.

[AHall]

Originally Posted by Oz M5

First, thanks for chiming in. Much appreciated.

No... When I press 'max-a/c' the blower goes to full power but the air only feels slightly colder than ambient.

My main concern is that when I press the auto button and the fan speed is set to high, even with the temp set to its lowest setting (16degC) and the cabin of the car feeling like it's over 38degC (100+F) the 'auto fan' blows minimally, as if the car thinks it's close to 16degC therefore doesn't need to work hard to lower the cabin temp.

If I then disable auto fan, I can manually increase the blower speed but like max a/c it blows air slightly colder than ambient.

The seat-blower is set to come on automatically for Temps above 25degC, however it's not coming on automatically. Again, points to a sensor issue.

All was working fine a week ago. I think she's just had enough of this brutal Houston weather!

Looks like I'll need to take her in for a diagnosis.

I definitely think a visit to your service center is warranted. Let us know how it turns out.

[Oz M5]

So took it into a local shop that specializes in BMW's and evacuated and regassed and added die to detect any leaks. Running cool again. Used a sniffer to detect any leaks and could not locate any. If it dumps the gas again they believe it may be the evaporator. Haven't got the quote yet.... but I'll be sitting down when I open it!!!

Time will tell!

Oh.... and no idea why it was blowing cold on the driver's side and warm on the passenger side 🙄

[RalphT5]

Interesting. I'm having similar bit slightly different issues. Mine will blow cold when I put it on Max A/C, but when I have it on auto, it will blow out HOT air in the feet area (even on 100F days in Houston). Car is due for service in 1500 miles or so and will get it looked at when it is serviced.

Don't know if it is related, but this started right after the latest software update.