[Supa Koopa]

I've been having the same issues others have experienced with the cabin seeming to go cold after a 20-30 minute drive. I thought I'd do a bit of digging to work out what was going on, so I bought a double temp sensor so I could measure the air temp in the cabin and from the air vent at the same time. As you'll see below my car is very optimistic on the air temp. As it should, the car pumped out warm air until it had heated the cabin and then it slowly started to feel cold as everyone reports, at this point I checked the temperatures.

As you can see in the first image the car thinks it's reached 20c, but it was actually 18c and was pumping out almost 21c through the vents, but with wind chill it felt cold.

Changing the temp to 22c resulted in a better temp of 20c and 26.5c air vent Temp.

So my car actually works correctly, as the air vent temp never went colder than the cabin, but the temperatures are just wrong leading to the confusion. It just means that as others are doing, I'm having to change the temp up and down depending on the day. I'm tempted to go to the dealers to get them to fix it, but they probably won't do anything.

Hopefully someone may find that slightly interesting, but maybe not.

[adam.b]

I have noticed that on cold day when heating is on, after heating cabin to set temperature with periodic times top wents will blow colder air for some time then go beack on warm/ hot air, it was in f21 1 series and f30/f31 3 series. When query this with sales person was told that this gimic is to prewent driver/passenders go sleepy.
It is more aparent when climate control is on auto.
I have same thing in ix3 and others bmw's I had in the past.

[GDEvans]

Surely all you are doing is demonstrating that the climate control is functioning correctly. Without knowing where the internal temperature sensor is located, it is impossible to know whether the car has reached the desired temperature. And it is unlikely to be in the phone charging area as there will be a sensor for both sides of the car.

Remember that climate control attempts to maintain a temperature within the vehicle - we are not setting the temperature of the air coming out of the vents. If the internal temperature is below the set temperature it will blow warmer air, and if it is above it will blow cooler air.

[Supa Koopa]

Originally Posted by GDEvans

Surely all you are doing is demonstrating that the climate control is functioning correctly. Without knowing where the internal temperature sensor is located, it is impossible to know whether the car has reached the desired temperature. And it is unlikely to be in the phone charging area as there will be a sensor for both sides of the car.

Remember that climate control attempts to maintain a temperature within the vehicle - we are not setting the temperature of the air coming out of the vents. If the internal temperature is below the set temperature it will blow warmer air, and if it is above it will blow cooler air.

Yes I realise this. What I was implying is that after a while the air coming out of the vents feels very cold as if it's stopped heating the air at all. Others have indicated the same problem, so I assumed the car was turning the heating off because it had reached the correct temperature and then never turned it back on. By doing what I did it demonstrated that this isn't the case as the air vent temperature never fell below the ambient temp even though it certainly feels like it does. I also realise this isn't where the temp sensor is located but it was the most obvious place to get an ambient air temp not affected by the flow of air. The footwells are our of the question, they always feel colder and higher up would be affected by the air vents. This just proved to me that the system is working despite my subjective feeling and saved mea pointless trip to the dealers. It also showed that setting the temp at 20c as I always do, including every previous BMW I've owned and the wife's minis, is not correct and I have to mentally get over having the temp set so high.

I just thought others might find it useful or interesting, my apologies if that isn't the case.

[Daimlermg]

Thanks that’s a good investigation, and as you say, saves trips to the dealer.

[Geordie EV]

Have you tried this test when in different driving modes? I feel the HVAC performs quite a bit better with the car in comfort or sport mode compared to eco pro. Obviously in eco pro the car is trying to conserve energy, which may be why you feel a drop in performance?

[BMWBataviaan]

So......all the complaining about a non existing temp problem can now stop!!

[Supa Koopa]

Originally Posted by Geordie EV

Have you tried this test when in different driving modes? I feel the HVAC performs quite a bit better with the car in comfort or sport mode compared to eco pro. Obviously in eco pro the car is trying to conserve energy, which may be why you feel a drop in performance?

Yeah I tried it in all modes and it made no real difference to the actual temps. What it did change was how quickly it warmed up when not in eco.

[Supa Koopa]

Originally Posted by BMWBataviaan

So......all the complaining about a non existing temp problem can now stop!!

Err, yeah if it makes you happier.

[sahajesh]

All I know is my previous BMWs managed the temperature better, so another fail with the iX3.

Only 760 days left with it…..

[silent ninja]

I get this problem too. I end up pushing the temperature up and down during a journey. It's really not good at automatically managing the climate. Odd for such an expensive car.