How to Reprogram an Alarm System

Locate the instruction manual that came with the alarm system to get the default installer code. If there is no manual, contact the manufacturer to get the code.

Go to the fuse box and trip the circuit breaker supplying electrical power to the alarm system's control box. Have an assistant stand by the breaker box.

Remove the screws from the cover of the alarm system's control panel, using the Philips screwdriver. The control panel is typically in a closet or out-of-the-way location, but not in the basement where it requires too much effort to get to in an emergency.

Pull the cover off the alarm system's control panel. If there are locking tabs or a hinge, push in on the tabs or swing the cover open before pulling it off.

Loosen the battery contact tabs on the top of the battery inside the control panel, using your fingers. Note which color of wire is wrapped around each screw.

Pull the lugs attached to the wires from around the tabs. Let five or six minutes pass. Place the lugs attached to the wires back around the tabs in the same way as they originally were. Tighten the screws.

Place the cover back on the control panel by reversing the procedure to remove it. Reattach the screws.

Call the family member on his cell phone. Tell him or her to flip the circuit breaker to restore power to the control panel on the count of three.

Count up to three. Press the "*" (star) button on the keypad at the same time as you press the "#" (pound) button when you say the number three. Tell the family member to close the breaker box cover. Release the keys on the keypad and disconnect your phone call.

Enter the installer code into the keypad to unlock the programming screens. Follow through the menu screens to reconfigure the alarm to match the parameters of the sensors installed.

Reset the default password to a password of your choosing. Return to the main screen. Enter your password to reactive the alarm system.