[marcthedark]

Hi,

Driving yesterday with my AC on and at some point I notice it is getting warmer.
There is still cold air coming out of the vents but just very little. Tried redirecting airflow to the windshield, feet, ... no change.
The sounds are correct > if I choose a higher fan speed the noise level increases as usual. AC on/off makes no difference to airflow.

My first guess is that the cabin filter might be blocked. Any other ideas?

[MarcoZandrini]

It doesn't sound like the cabin filter is blocked as you'd see decreased flow over a long period of time. Of course, something could be blocking the filter. Your climate control module (IHKA in BMW speak) could be an issue. Does the outside temperature displayed in the gauge cluster seem accurate? The IHKA uses the ambient (external) temperature to help manage the interior climate.

[marcthedark]

The outside temp looked about right. Maybe a few degrees low, but we would be talking 88 vs 92 degrees
Maybe the mechanism that would control the airflow (window/feet/...) is not working. Any quick way to test this?

[Ajowhan]

Originally Posted by marcthedark

Hi,

Driving yesterday with my AC on and at some point I notice it is getting warmer.
There is still cold air coming out of the vents but just very little. Tried redirecting airflow to the windshield, feet, ... no change.
The sounds are correct > if I choose a higher fan speed the noise level increases as usual. AC on/off makes no difference to airflow.

My first guess is that the cabin filter might be blocked. Any other ideas?

AC on/off makes no difference to airflow and never have. Airflow is controlled by fan speed. Assuming the sounds are correct, higher fan speed = higher noise level = higher air flow, the problem is definitely not with the air filter.

With that, 2 possible causes comes to my mind.

1. Your refrigerant/Freon is low and needs to be recharged or there might be even be a leak. Recharging is pretty simple.

2. Radiator fan fail. This could be bad for your car as the fan works on both cooling the engine and your AC.
(This is the one that actually hit my wife car, I am ashamed to say I actually told her that the AC is not too bad, and she insists it should be cooler. We ended up checking it and found 1 of the radiator fan wasn't turning. Luckily in our case, it was only a blown fuse. Replaced fuse and it came back on.)

[marcthedark]

Originally Posted by Ajowhan

AC on/off makes no difference to airflow and never have. Airflow is controlled by fan speed. Assuming the sounds are correct, higher fan speed = higher noise level = higher air flow, the problem is definitely not with the air filter.

With that, 2 possible causes comes to my mind.

1. Your refrigerant/Freon is low and needs to be recharged or there might be even be a leak. Recharging is pretty simple.

2. Radiator fan fail. This could be bad for your car as the fan works on both cooling the engine and your AC.
(This is the one that actually hit my wife car, I am ashamed to say I actually told her that the AC is not too bad, and she insists it should be cooler. We ended up checking it and found 1 of the radiator fan wasn't turning. Luckily in our case, it was only a blown fuse. Replaced fuse and it came back on.)

Where is the fuse box (I should know but somehow ....)?

[marcthedark]

So I went out and found the fuse boxes and the diagram .... started to pull the ones related to the AC and the Fan symbol. They all looked good.
So I started the car and air was coming out of the vents as usual. Turned on the AC and cold air was coming out.
How did the car fix itself overnight? Any best guesses on what it was and what to do about it (if anything)?
BTW opened the hood and the radiator fan was spinning

[este]

Probably a leak. I had a small one on the Ac condenser and had same symptoms of not staying cold. I decided to just recharge instead of changing ac condenser and Ac has stayed cold for about a year.

[marcthedark]

Originally Posted by este

Probably a leak. I had a small one on the Ac condenser and had same symptoms of not staying cold. I decided to just recharge instead of changing ac condenser and Ac has stayed cold for about a year.

Anything I can check? Or can the coolant level only be seen by BMW?

[aerobod]

You may also be suffering from freezing of the evaporator, a problem with a number of last gen 3 & 4-series cars, but also I believe seen in some 2-series, as the system is fundamentally the same: https://static.nhtsa.gov/odi/tsbs/20...47832-9999.pdf The fix for later cars (built after 2014) was a coding update to raise the minimum evaporator temperature.

[marcthedark]

Originally Posted by aerobod

You may also be suffering from freezing of the evaporator, a problem with a number of last gen 3 & 4-series cars, but also I believe seen in some 2-series, as the system is fundamentally the same: https://static.nhtsa.gov/odi/tsbs/20...47832-9999.pdf The fix for later cars (built after 2014) was a coding update to raise the minimum evaporator temperature.

The conditions fit the linked paper ..,. Outside 90 inside set to 66 (not that it reached it) and it happened 1h+ into a 2.5h trip.
Wonder if there is a recall or so for a 2017 M240 as the car is outside warranty and this needs to be fixed (as I will relocate to AZ where this might happen a lot).

[este]

Originally Posted by marcthedark

Anything I can check? Or can the coolant level only be seen by BMW?

I got it checked through bmw under warranty. They use a coloring style agent put into AC system to check for leak. Most time too small to see by eye.

[aerobod]

Originally Posted by marcthedark

The conditions fit the linked paper ..,. Outside 90 inside set to 66 (not that it reached it) and it happened 1h+ into a 2.5h trip.
Wonder if there is a recall or so for a 2017 M240 as the car is outside warranty and this needs to be fixed (as I will relocate to AZ where this might happen a lot).

I would try and have a friendly conversation with the dealer, mentioning the conditions in the TSB and saying although it doesn’t cover your car directly, the conditions are exactly the same and would they have seen this sort of issue with the 2-series? As it is a common issue, they may be willing to cover it under goodwill.

You may also have less issues in a dry climate such as Arizona, as it seems to be a lot more likely in high humidity environments where the high moisture in the air forms ice quicker.

[MarcoZandrini]

Originally Posted by marcthedark

Where is the fuse box (I should know but somehow ....)?

There are fuse panels in the trunk.

[marcthedark]

Originally Posted by MarcoZandrini

There are fuse panels in the trunk.

Found them and the little paper chart ... that one pointed me to the additional fuses in the engine compartment. Fuses all over the place

[luke335ix]

Originally Posted by marcthedark

Hi,

Driving yesterday with my AC on and at some point I notice it is getting warmer.
There is still cold air coming out of the vents but just very little. Tried redirecting airflow to the windshield, feet, ... no change.
The sounds are correct > if I choose a higher fan speed the noise level increases as usual. AC on/off makes no difference to airflow.

My first guess is that the cabin filter might be blocked. Any other ideas?

I just had the exact same problem It's 95 degrees out, and I was out driving around and noticed it getting warmer in the car. I could hear the AC air blower working hard, but there was very little air flow coming out of the vents (air was still cold).

I took out the cabin air filter, and found no obstructions. After I put the filter back in, the cold air was back to flowing normally.

Has anyone determined what the issue could be?

[aerobod]

Originally Posted by luke335ix

I just had the exact same problem It's 95 degrees out, and I was out driving around and noticed it getting warmer in the car. I could hear the AC air blower working hard, but there was very little air flow coming out of the vents (air was still cold).

I took out the cabin air filter, and found no obstructions. After I put the filter back in, the cold air was back to flowing normally.

Has anyone determined what the issue could be?

Usually a frozen evaporator.

[luke335ix]

Originally Posted by aerobod

Usually a frozen evaporator.

Thank you, that's sounds correct based on the symptoms.

[TrboMike]

For some reason my girlfriend likes to drive around in her car with the A/C set to 60 and the fan on the lowest setting no matter what temp it is inside or outside the car. She freezes her condenser all the time and no more cold air from the vents. She wants to bring her Honda to the dealer to "fix it" and she cant understand that she's doing it wrong and gets mad at me.

I should get out while I can. No, she's not allowed to drive my car.

[dradernh]

Originally Posted by TrboMike

I should get out while I can.

That was certainly my first reaction!

[delvec03]

there's a spacer for the F30 models that fits on F22 for evaporator coil temp sensor that solves this issue. search on the F30 forums. it's an easy fix