How to Program Your 2004 Hyundai Sonata Keyless Entry System
- 1). Enter your vehicle with your remote and ignition key and close the doors of the car.
- 2). Turn the car to the "On" position, press "Lock" on your remote and then turn the ignition back "Off."
- 3). Repeat the previous step three more times and end on "On" after the last cycle. Press "Lock" on your remote again and wait for the locks to sound (make a noise as they cycle).
- 4). Press "Lock" again to program the remote within five seconds and wait for the locks to sound again.
- 5). Repeat step five with any additional remotes and remove the key from the ignition once you have finished.
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