Press the lock cylinder that is locked and hear the toot sound, the lock has entered the alarm state, 15 seconds later, when the lock or the car again by the vibration that is issued toot, toot, toot 3 alarm, and then continuous vibration, continuous alarm, each alarm sound lasts 10 seconds. The alarm will last for 10 seconds each time. When replacing the battery, use the equipped small wrench to turn out the 4 screws, remove the top cover can be replaced, please pay attention to the batterys positive and negative poles. Please note the positive and negative polarity of the battery. Important Reminder: In order to facilitate the replacement of the battery in the future, please keep the small wrench and the instruction manual.