The Mégane II Owners' Club

my car battery was disconnected sat since it going ok again my cd player does not switch on

Is it the original Renault-fitted Tunerlist or Updatelist radio/cd? If so, it is probably wanting you to enter the security code. Does it not show "Code?" (or something similar) on the display?

I'd say that's the problem. If you don't have the code, (ie second hand car) you can just call any Renault dealer and give them either the Reg number or VIN and they can get the code for you.