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The Daily Insight

What does OC mean on my alarm system?

Author

David Ramirez

Published Feb 15, 2026

What does OC mean on my alarm system?

OPEN CIRCUIT (or OC): The Keypad is not communicating with the main control panel. Long Rng Trbl (or bF): If installed, there is an issue with long-range communication.

Why is my alarm panel beeping?

Most alarm systems have a backup battery that kicks in if the power ever goes out. When the battery is low or dead in an old alarm system, the system will start beeping to alert you that it needs to be replaced. If your battery is low, it will either need to be disconnected or replaced.

What does OC mean on Honeywell alarm?

oc = open circuit = keypad is not receiving data from the panel. check the wiring on both ends (yellow and green are data). AC power failure on your security system means that the system is not receiving plug-in power from a wall outlet. To remain powered, the system has switched to its backup battery.

What is a telco fault?

“Telco Fault” is a message that indicates that something may be wrong with the system’s telephone communication. Until this problem is dealt with, the system may be unable to send out any communication signals to a central station.

How do I reset the FC code on my alarm?

You can clear the FC code on your Honeywell alarm by entering [Installer Code] + [800] + [*41*] + [*42*] + [*54] + [#15] + [*55] + [1] + [*99]. This will clear the phone number that was programmed. It will also adjust the dynamic signaling settings for the panel to prevent future FC messages.

How to change the codes on a Honeywell alarm grid?

A panel with a numeric keypad, such as a Honeywell Vistaor an L3000, will have a different process than a touchscreen system, like a Lynx Touch panelor a Lyric Controller. Any user code, including the Master Code can be changed on a Honeywell system at any time.

How to turn off the chime mode on a Honeywell alarm?

How to turn the Chime mode off on your Honeywell alarm system: Key in your four-digit security code. Press 9 (CHIME). The Chime message will be removed from the screen.

Why does my Honeywell alarm keep going off?

This is the case when you see a CHECK 70 or BELL FAILURE display (on Vista 15P, Vista 20P, and Vista 21ip systems) or FAULT (on Lynx Plus systems) display. This trouble condition indicates a faulty wiring connection to the external sounder. Check the condition of your alarm system’s wiring.

What is the master code on a Honeywell alarm?

The most common are outlined below: Master Code: Each system has one Master Code. This is the main code a user will normally use for arming and disarming. It can perform all security functions, add and delete users, change the current Master Code and perform many additional system functions. This code cannot be deleted from the system entirely.

This is the case when you see a CHECK 70 or BELL FAILURE display (on Vista 15P, Vista 20P, and Vista 21ip systems) or FAULT (on Lynx Plus systems) display. This trouble condition indicates a faulty wiring connection to the external sounder. Check the condition of your alarm system’s wiring.

How to turn the Chime mode off on your Honeywell alarm system: Key in your four-digit security code. Press 9 (CHIME). The Chime message will be removed from the screen.

The most common are outlined below: Master Code: Each system has one Master Code. This is the main code a user will normally use for arming and disarming. It can perform all security functions, add and delete users, change the current Master Code and perform many additional system functions. This code cannot be deleted from the system entirely.

How do you disarm a Honeywell Security keypad?

Disarm the system twice. Key in your four-digit security code. Press 1 (or the OFF key). Do this step again. The green READY light will then turn on. Arm your system. Key in your security code and press 2 (or the AWAY key). The keypad will beep twice and display the Armed message. Keep your Honeywell security keypad working fine all the time.