Please help with a Philips radio unlock PIN?

Hi,

My friend bought a car but wasn't given the PIN for the radio - battery has just been replaced, and she can't get the radio working anymore.

The radio is:

Philips Model 79RC600/95 Serial No PH600C10375759 Production No CG0101490375759

Would be greatly appreciated if somebody can provide the PIN for this? Or explain how it is derived (is it some hash of the serial number?)

Thanks