Making sure the batteries are good is the 1st step.
Then getting into the car, shutting the door, pointing the remote at the mirror, pressing the button on the key twice, inserting the key into the ignition, turning the key to position 2 & then off, removing the key, pointing the key at the mirror again, & then pressing the button on the key.

That is the ONLY programming of the key..synchronizing is a better description.

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