2005 gmc sierra, replaced radio with known good radio with same part # and model #, all functions work but there is no sound from the radio or the key and door chimes. Is this a lock feature. Took vehicle in to the dealer to reprogram radio to my vehicle and I am being told there should be no display on the radio other than LOCK. Will reprogramming cure my ill's.

I cannot understand how you radio would work. These radios are coded throught data link to computer. the only way to get the stereo to work is to run a calibration program through the vehicle. then it should accept your new cd player. if the stereo's are the same then may I suggest you to take the radios appart and switch the parts that don't work like CD drive assembly and faceplate.but use your factory installed stereo as the main core, this should fix your isses and work fine since the calibration is for the origional factory stereo.