Quick answer
A fault light or message on your keypad means the alarm has found a problem with itself, most often mains power, a low battery or one detector, and you should read what the panel says, note it down and clear it rather than leaving it showing.
A fault is the system doing its job: telling you something needs attention before it affects your protection. Most faults are minor and clear easily once you know what the panel is reporting.
Read what the panel is telling you
Your keypad will usually display a code or a short description, and many panels will also show the zone or device involved. Write down the exact wording before you clear it. The most common messages are these.
- Mains fault or AC fault. The panel has lost its 230V supply and is running on its standby battery. Often this is a power cut, a tripped breaker or a switched off fused spur.
- Low battery or battery fault. Either the standby battery in the panel, or the small battery in a wireless detector, keyfob or external sounder. Wireless devices normally name themselves in the message.
- Tamper. A cover has been opened or a lid screw has worked loose, on a detector, keypad, sounder or the panel itself. Wind rocking an external sounder can do it.
- Detector or zone fault. One device is not answering, or is reporting a problem with itself. A masked detector message means something is blocking its view.
- Communication or line fault. The path to a monitoring centre or app has dropped, commonly after broadband or router work.
- Supervision or jamming on a wireless system. The panel has not heard from a device recently, or radio interference is present.
What to check first
- For a mains fault, check whether other electrics in the building went off, look at the consumer unit, and confirm the alarm’s fused spur is switched on. Its neon is easy to knock off during cleaning or decorating.
- After a long power cut, a low battery warning will often clear by itself once the mains has been back on for several hours and the battery has recharged.
- For a tamper, look at the named device and check its cover is fully closed and its screws are tight.
- For a detector fault, check nothing has been stacked, hung or parked in front of it, and that a shelf or seasonal decoration is not touching it.
- Enter your user code to silence and reset. A one-off fault normally clears at this point.
Do not pull the panel’s fuse or disconnect the battery to silence a fault, and do not leave the system unset for days because the keypad is beeping. Both leave you without protection, and disconnecting a panel can flatten a battery that would otherwise have recovered.
The standards behind your system
Intruder alarms in the United Kingdom are normally designed and installed to BS EN 50131 under the PD 6662 scheme. Those documents set the grade of the system, the standby power it must hold and the maintenance regime that keeps it certified. How often your system needs a service depends on its grade and on whether it is monitored, so a system with a response through an alarm receiving centre is inspected more often than a bells only system. Your service record should be kept with the system log.
When to call an engineer
Call us if the same fault returns after a reset, if a battery warning does not clear once mains power has been restored, if a detector or tamper fault names a device you cannot reach or inspect, or if the panel reports a communication fault and your system is monitored. Advanced Overwatch is SSAIB certificated (NIRE127) specifically for Intruder Alarm Systems, Visual Surveillance Systems (VSS) and Access Control Systems. We have looked after systems across Northern Ireland from Coleraine since 2017. Call us on 028 7087 8077 to arrange a service visit.
Related reading
- Service page: Intruder alarm installation in Northern Ireland
- Related guide: How can I stop my intruder alarm giving false activations?
- Related guide: How to Choose the Right Intruder Alarm for Your Northern Ireland Home
- All of our guides: Knowledge Base