What car is it in and is it the original unit to the car? If its a renault use the remote control on the steering coloum, use the wheel to change the number and then press 2 on the radio to input the 2nd and so on until you have done it 4 times and then hold down number 6 button or number 5 i forget and it should be where you left it before on radio 1 or cd.
Rich
January 2005