2000 Buick Cent Radio TROUBLE

My wifes Buick bought new in 2000 Radio is now locked out. pulled a fuse
by mistake.
We never entered a code for the radio when we got the car ????
Does anyone know the reset code
Thanks , Larry

Have to go to the dealer to get unlocked!

Thank you Flatrater
Larry

Interesting. Does that also mean that if I was to re-install the stereo I took out of my 2000 for an aftermarket, it would not work without this code thing?