Why is My BMW AC Blowing Warm Air?
As we drive through the peak July heat of Summer, one question I’ve been hearing a lot from my subscribers is about your BMW air conditioning system issues. There are three really common issues across all BMW’s with respect to inoperative or weak AC problems: The center control knurled stratification wheel knob is poorly adjusted The electric auxiliary fan behind the front bumper has failed The AC freon leaked out and needs a recharge of 134a The first place to start diagnosis is the easiest: check your center control knurled stratification wheel knob in the center of the dashboard. Every BMW since 1980-something has one. And it may be the most misunderstood HVAC control knob of any German car out there – even today! Here’s a background on how this HVAC control knob works and why it could be causing you to have warm air blowing in the Summer and air too cool blowing in the Autumn and Winter. The often overlooked stratification knurled wheel for the center vent is often the cause of heating …