How to Remove the BMW A/C Knob
1. Grasp the edges of the left AC knob with your fingertips and gently pry the housing away from the knob itself until the housing pops off.
2. Unscrew the screw found underneath the knob housing with a No. 5 screwdriver. Keep the screw handy for your replacement or re-attached knob.
3. Repeat the above procedure with the right knob, then push the climate-control panel forward and slide it downward to remove the knob housing. Replacement knobs can now be fitted into the panel, or the original knobs re-attached if they are in need of repair.