All modern-day BMWs have a dedicated windshield defrost button. Humid mornings when condensation occurs or a sheet of frost in the winter can often cover your windshield requiring the defrost function to be turned on. With the press of a button, the car will automatically configure the blower fan speed, temperature, and vent direction. Within minutes, one is able to see clearly through the windshield and drive safely on the road. Older BMW models from the 80s and early 90s do not feature this button in comparison.
Most E30 or E34 owners may think their vehicle does not have defrost due to the lack of this button. The defrost feature is in fact still part of the vehicle, but the configuration is not easily recognizable. There exists a small diagram displaying the "code" or dial settings for the defrost function on the E30 and E34 models. Please see the images below for clarification.
Where is the diagram located?
E30: Below the A/C, recirculated air buttons.
E34: Between the blower fan speed dial and temperature setting dial.
What are the settings?
- Vent setting up, full open.
- Vent setting on face, closed.
- Vent setting on feet, closed.
- Fan speed, max.
- Temperature, max heat (dual climate on E34).