Tried to crank up the heater one day but I could only get luke warm temps out of the system. How do you adjust the temps? The knob with the temps only go up to 80 degrees? No luck in the I-drive so far. Any thoughts before I freeze my rear off? I do know how to use the seat warmer. :-))
2009 535i, premium, sport package w/paddle shifter, navigation etc.

 

Press the center of the fan switch. This will bring up a temp dial on your idrive screen which you adjust with your i drive.

 

Thanks! Sounds pretty simple!

 

To add to that reply, that adjusts the center vent temperature. That's useful for blowing cooler air at night to avoid making you drowsy.