How to Program the Keyless Entry System on Your 2004 Hyundai Sonata
- 1). Sit in your 2004 Sonata's driver's seat with your keyless remote and ignition key in hand.
- 2). Turn the key to the "On" position, press the lock on your remote and turn the key back to the "Off" position.
- 3). Repeat the process from step 2 three more times, for a total of four cycles, and end the fourth cycle in the "On" position.
- 4). Press the lock button on your remote and wait for the locks to sound to indicate the beginning of the programming sequence.
- 5). Press lock on your remote and wait for the locks to indicate successful programming. Do this within five seconds.
- 6). Repeat step 5 with any additional remotes and remove the key from the ignition to end the programming sequence.
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