asking for code

installed new air mass sensor and car runs better than ever. when i turn on the radio ( CODES ) appears with the (C) flashing continuously . not knowing ( stupid ) i hit #5 on presets and now i have 5_ _ _ _ _ . can anyone tell me how to clear and install correct code it is asking for . when i installed new sensor it wouldn't crank - disconnected ground to battery for approx. 2 min. connected ground - car cranked and has run perfectly . but , i am fearful of driving because of code . can you help and will it damage car to drive without code ? please help if you can .
J.D.

[300EVIL]

Due to your battery disconnection the radio is asking for its anti theft code. You can try looking in your owners manual for the new code, i found mine in there, the dealer will scrible it in with a pen usually. If not, then you have to go to the dealer to retrieve your radio's code. They will need the VIN no. to look it up. Also, some dealers require some verification of ownership before they will give you that info, be prepared!
Good Luck,
Adam