2001 Mercedes Benz 320e

The windows an sunroof need to be renormalized. Roll the window up and hold the switch in the up position for each window for 10 sec. As for the sunroof with the sunroof closed hold the switch in the forward position. The code means you need to enter your radio code. This should be located on a business card size card in your owners manual. Enter the number on the card and hit the tuner knob. If you don't have it you may have to go to the dealer to have them source the code against the radio part #.