My 98 deville am/fm cassette bit the dust and I bought another from a salvage yard.The display says lock and I've tried and tried pushing buttons to get codes but can't get anything to work. I've read in the past about lifting a pin on a eeprom, but can't seem to find the info again. can anyone point me to it?

You try the hold down the 2 and 3? If it doesn't work those keys may be bad. The gm radios are not the best quality

See if this helps you out any.

How to Unlock Your Locked GM Theftlock Radio: 11 Steps

I did try the holding down the buttons like in the instructions, but no change. The display doesn't say loc but does say lock. I've heard that would work on an origonal radio, but didn't know if it would work on a replacement radio.

Maybe it is not a Delco model that those methods work for, if it is not then you may want to just consider getting an aftermarket deck, as it won't cost much more than what you are going to pay a GM Tech to unlock it.

you spend 120-130 at sonic electronics you get adapters, mounts, free shipping, etc. i got a HD, usb, everything sony, its a million times better than any delco

I guess I'm just too much of a cheapskate to go to the dealer or spend on adaptors. lol

if you bought it from a yard they should at least let you exchange it, but dont be surprised if you have to try a few, the delcos just suck and why i always buy a aftermarket one, they last a billion times longer, and have all the modern features

Step #3,,,,the wording and the picture doesn't match....you press 2 and 3 presets, not 1 and 2....

Also the radio has to be an exact match, and same year......a "2000" radio, or newer, needs a Tech II to unlock it...so if you are trying to install a 2000 radio instead of a 1998, that procedure won't work.....

Ha ha, whoever illustrated that was a few sandwiches short of a picnic, good catch Gus!