yogibear458

sorry to post a newbie question after owning the car for more the 2 years. How do you set the cabin temperature when you need to turn on the windshield defrost? I was driving the car yesterday , it was cold and snowing. (I didn't drive this car in the last 2 winters) so I turned on the front windshiled defroster, the fan hit its rev limiter so I turned it down a bit, but the inside of the car was getting really hot. I tried turning the temperature dial but it has not effect.

Is there something wrong with the temp control or is there a way to run the ventilation system with hot air going to windshield while regulating the interior temperature?

thx

Rudy

The defrost program is kind of an all out "assault" on the windshield so when you press the defrost button, the goal is to heat it as quickly as possible to defrost it and allow you to return to a normal mode. Do you happen to keep your fresh air circulation closed all the time? (That's generally not a good idea to do.)

In my experiences with the car, rarely do I need to use the defroster but when I do, it works perfectly. Usually, I keep the climate control set to full auto (including the fresh air vent) and the car does the rest...

The car is smart enough to monitor condensation, etc. Here's an excerpt from the A/C system (IHKA) Basic and High document I posted in the technical gallery that mentions some of this stuff:

How it works
The condensation sensor is only active when the IHKA is in automatic mode.
The condensation sensor indirectly exposes condensation on the window surfaces. In other words, the condensation sensor
monitors the environment in which condensation forms on the window surfaces. Humidity on the windscreen and the temperature of
the windscreen inside the vehicle are measured and a frequency-dependent signal is generated.
To measure the atmospheric humidity, the condensation sensor contains a capacitive sensor element. The sensor element is a
component of an electrical oscillation circuit. The oscillation circuit is detuned in proportion to the change in humidity at the
windscreen. The resonant frequency of the oscillation circuit is then used as a reference to measure the air humidity. The IHKA
control unit evaluates the frequency-dependent signal. Moreover, the interior and exterior temperatures and the temperatures of the
windscreen inside the vehicle are evaluated.
If an air humidity of more than 65 % is detected at the windscreen, the IHKA control unit will initiate measures to prevent
condensation on the windows .

den535d

COOOOL

coolguy

Fresh air Ventillation/circulation is the one with 'A' right? I have same thing in mine, all the 3 green lights lit all the time. Is this the way to have it during coldweather? So when do you use the Defrost for the font windshield? Its not automatic is it? Thanks

Rudy

All three lights straight in a row is full auto (yes, the one with the "A" is auto recirc).

I use defrost when the windshield fogs up which is usually never...I don't think it'll turn on full defrost if the window goes full fog -- the idea, I think, is for the system to automatically maintain a good level of humidity without condensation developing on the glass and in my car, it seems to work very well...

coolguy

I am asking about cleaning the Snow off windsheild though... not for Fog, I never seen fog in mine so far. I know the side-mirrors are Auto-heated, but not sure about the windsheild. (I have 2006 525i with Premium/cold packages)

yogibear458

I use front defrost to prevent ice and slush from forming on the outside of the windshield.

Is there a way to direct hot air to the windshield and the footwell with temp control ? I dont want to take off my winter coat while driving - something I can do with my GTI which has a manual dial for temp and vent distribution - come to think of it, most cars have such a setting!

dlevi67

Yes, the automatic programmes already direct air to the windscreen as well as footwell and face air vents. If you want to change manually, choose Climate / Air Distribution from iDrive and you'll see that on the driver's side there are three horizontal bars indicating (top to bottom) flow of air to windscreen, face air vents, footwell. Play to your heart's content, but I'd be surprised if you can get a result that is significantly better than the automatic programmes.