Hello & Welcome,
Can you tell us the Model of your Caddy?
Can you also tell us the 8th character of your VIN? It should be a 9 or a Y.
Here is the procedure I have.
I hope this helps. Please let me know if you need more information.
Take Care & Good Luck, Greg A.
This looks like it may be the answer.
Give it a try and let me know how it goes.
Take Care, Greg A.