My Mercedes C280 went for service. After the service when I enter the unlock code of radio I see message waiting on the consol of the radio. I think I enter a wrong code. How to reset the radio?

An answer to your question according to the book you are to turn the radio on and leave it on and you will see the message(waiting) it will stay like that for 15 minutes then the sreen will turn to code which at this point you may enter the code and it will work again. Good luck. In case you lost your code and unless you know the radio serial number (you can remove the radio and see the no behind the set) the fastest way to get your code back is to go to www.radio-code.co.uk. Follow the instruction and for 8.99 british pound (yes you have to pay for the service) you will get the right code instantly. It works for my BECKER car radio. Believe me it works.