2002 BMW M3: Hot or Cold?
June 01, 2009
See this little knob between the M3's center dashboard vents? It controls the air temperature coming out of those vents and the two outer vents by the doors. And it does so with authority over the enitre automatic climate control system. Why this is silly after the jump...
Dialing this little knob to full hot or full cold will give you exactly that regardless of what the rest of the system is trying do. This is a great thing if, say, you like your feet to be 90 degress and your hands to be 60 degrees. But, overall, it's cumbersome, unnecessary and, oftentimes, confusing.
The manual isn't any help. It points out that one can turn off the airflow through these vents with the outer knobs (1) and adjust its direction with the tab in their center (2). But it fails to mention that by moving the center knob (3) you can completely contradict what you're trying to accomplish with the primary climate controls.
Certainly, this can be an interesting fine-tuning tool for cockpit comfort, but, more often, I find it frustratiing -- like when I jump in the car on a cool morning after parking in hot weather the day before. Naturally, in hot weather, I had the vent temperature control set to cool (or, more often, another driver did). Now, however, it's 50 degrees and I want hot air.
What do the vents do? They blow cold until I reset the knob. I don't get it. And that's just when the system is set to "automatic." Combine this knob's abilities with the mode controls, which allow selectable airflow to the windshield, center vents or foot area and you can make some truly self-defeating things happen with cockpit temperature.
I'm sure there's no shortage of fans of this "feature" out there. But the way I see it it's just another adjustment I have to make before I find comfort.
Josh Jacquot, Senior road test editor @ 72,300 miles.