sony car cd player

[mitsy]

I have got a sony car cd player, but my car has been off the road for a while!! Now I have decided to do it up and sell it, the only thing is the battery had died and lost the code for the cd player. I had the intructions on how to put the code back into it, it was on a yellow sheet but I am unable to find it, there is a series of buttons on the remote to use, how can I find out what the code is, for me to use the cd player - many thanks in advance