how can i fix my Philips car stereo installed in Vauxhall Corsa?

hi,
i changed the battery of my 2nd hand car and now i don't have the code for the tape, neither i don't know how to feed it in stereo.
kindly help.
stereo is made by Philips, it's no is 90381124, its type is SC 201 (C) and it is made in Germany
it has got two barcode at it which are :
1. 90222146075802
2. 00095041604222

waseem Shuja
June 2005