How do you reset Mercedes w140 radio?

To reset the Mercedes W140 radio, turn the ignition key to the "On" position without starting the engine. Press and hold the "Reset" button, typically found on the radio's front panel or inside the faceplate. If the radio has a code, you may need to enter this code after the reset. If you don’t have the code, consult your vehicle’s manual or contact a dealership for assistance.