: Excessive heat in footwell

06-15-2012, 06:32 PM
Something went kaphooey with my climate control system. I now have full heat coming out of a vent over the feet in the footwell. A/C is running in center vents and across windshield. If I turn on the individual climate options, the two little angled vents on either side of the dash, maybe 8" from side, also blow hot air.
I wonder if it is some sort of control module.
This is happening at 75-80F outside, so I really don't need to roast my legs as we head into full blown summer.

The same thing happened in my old E39 540. A mechanic fixed it by forcing a valve shut, but i could still feel a bit of heat. I am not going to tolerate it on this car.
Anyone had this happen?

06-16-2012, 07:29 AM
My e39 did it as well, same solution. My suggestion would be to cycle your iDrive (after the car is completely warmed up) through hot to cold comfort settings, and also to cycle ther main controls through hot and cold several times; this may force a stuck valve with hot coolant. If that doesn't work, hit up realoem and find out how many swap-valves we have; I know that they're not too hard to get to under the filters.

06-17-2012, 04:46 PM
Thanks. tried turning temps up and down. It affect the amount of air that is being pumped into the footwell, but does not turn heat off, ie temperature of the air is the same super hot.
I will have it diagnosed. Maybe we can pull an error code from Autologic. Else will have to investigate the plumbing for airflow and controls.

06-19-2012, 11:46 AM
Update. The car is now back to normal operation without my doing anything. I got it scanned with Autologic and it posted error codes for the solar sensor that sits on the windshield by the rear view mirror.
Today was sunny and low 70s. AC blowing normally. When i had the excessive heat in the footwell it was raining and dark out.
I will wait to see if the problem reoccurs on a different day.
This is one of those issues that can be very problematic, because the solar sensor may be fine and the problem related to a downstream effect. We'll see.

08-30-2012, 07:54 AM
This problem reemerged and seems to be getting worse. I deal with it by using the individual climate control settings and only letting center vents blow.
I have gotten zero feedback from the user community, but have spoken with a number of BMW service managers and techs. The general feeling is that I may be low on freon, and when that hapens the climate control system directs cold air only to the larger vents and shuts the others off. This causes hot air to enter the other vents.
If the car is not low on freon, then it is most likely the stepper motor, which is a unit deep inside the dash that controls the flaps to open and close various vents.
I'll keep posting updates and hopefully a successful resolution soon.

I bought my car used from BMW in Orlando, FL, so it would not surprise me if the A/C system could have lost some pressure due to constant operation for over 3 years.

08-30-2012, 07:58 AM
Best of luck getting this sorted out.