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You need a Hyundai Scanner to reprog. the key fog.Thank you again for trusting us with your problem. Please reply as soon as possible so that we can finish answering your question.
Hello, my name is Glenn
Welcome to JustAnswer.
I'm not sure what you've been told, but it contradicts what the published service information from the HYUNDAI service website.
Click HERE to download this document.
You can re-register after replacing the battery, but as far as I know, registering a new fob requires a HI-SCAN tool.