Radio has no sound. on 1998 Cadillac Catera

Radio has no sound. It lights up and you can change the stations. Checked fuses on drivers side. The manual that comes with the car does not show how to enter the code. Also were is the amp loc. Thank you.

Asked by for the 1998 Cadillac Catera
yes my radio has no sound. one day i unplug my radio to try another radio that came out of car just like mine same modle it didnt work so i put mine back in and it work. like always i just wont a cd player in mine. now my sound went out after one week i put mine back in. one day i came home from work my didnt have no sound it lights up and you can change the stations to but no sound can you help me.
i went through the exact situation in my grandmothers catera. she had no sound or power to the radio and she couldn't open the fuel door or trunk unless she had the vehicle running and left in Drive. I recently decided to either tackle these issues or sell it and found it to be a problem with a relay switch "k134A" I purchases a used one on ebay (since a new one priced over 1000) and it is a simple unplug old/ plug in new installation. Fixed instantly.
3 more answers , 1 more comment
Try this disconnect the battery which will then reset the computer upon reconnection, I think this radio has a door chime that runs through it.
what do i need to do now.
u need a new batt.
if no sound with simple hook up to a known good is no good