Hyundai Elantra MD/UD: Lock (1)
All doors are locked if the lock button is pressed. If all doors, trunk and hood are closed, the hazard warning lights will blink once to indicate that all doors are locked. Also, if the lock button is pressed once more within 4 seconds, the hazard warning lights will blink and the horn will sound once to confirm that the door is locked.
However, if any door, trunk lid or engine hood remains open, the hazard warning lights (and/or the horn) will not operate. But if all doors, trunk lid and engine hood are closed after the lock button is pressed, the hazard warning lights will blink once.