Try leaving the battery unhooked for 12 hours. The Passlock system that GM uses is a real pain sometimes. If you get lucky, 12 hours without power will reset the memory and you'll be able to use your key again. This worked for me once on a Chevy Venture I was installing a remote starter into.
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Try leaving the battery unhooked for 12 hours. The Passlock system that GM uses is a real pain sometimes. If you get lucky, 12 hours without power will reset the memory and you'll be able to use your key again. This worked for me once on a Chevy Venture I was installing a remote starter into.