How to Reset an Ademco Alarm After Replacing the Battery

Observe the master console of the Ademco alarm system. The "Low Bat" light is illuminated when the system needs a battery replacement. The display on the master console shows a number of the sensor that needs a battery. If your system is disarmed, the master console emits fast pulsing beeps. If your system is armed, there are no audible tones.

Replace the 9-volt battery in the affected sensor on the master console display.

Enter your access code on the nearest console or keypad to the alarm system. Press the "Off" key. The red "Home" light will go off and the green "Off" indicator will light, showing that the system is disarmed. You will hear one beep to verify that the system is disarmed.

Activate the sensor that you replaced the battery in. Open a door or window to activate an exterior sensor. Walk in front of a motion detector inside your home to activate it.

Enter your access code on any console or keypad of the alarm system. Press the "Home" or "Away" button to arm the system, then immediately enter your access code and press "Off." This action will reset the alarm to illuminate the low-battery signal to the system. The "Low Bat" indicator will go off, and the sensor number will be erased on the keypad of the master console.