Your alarm panel is showing a “Comms Fault” or failing to send test messages to your mobile app. If you are asking, “Why is my alarm system not communicating?”, the issue is almost certainly related to the cellular GSM connection.
Here is a professional troubleshooting guide to get your panel back online.
1. The SIM Has Been Deactivated
If you used a standard Pay-As-You-Go SIM (from a high street shop), the network has likely deactivated it. Consumer networks cut off SIMs that haven’t made a chargeable outbound call in 90 days.
- The Fix: Remove the SIM, put it in a phone, and try to make a call. If it fails, the SIM is dead. Replace it with an Anywhere SIM M2M card, which is exempt from inactivity deactivations.
2. Faraday Cage Effect (Metal Enclosures)
Many professional alarm panels are housed inside thick metal control boxes to prevent tampering. Metal blocks cellular radio waves. If the GSM antenna is located inside the metal box, the signal will be terrible or non-existent.
- The Fix: Drill a hole, run a coaxial cable, and mount an external GSM antenna outside the metal enclosure.
3. Single-Network Outage
If the panel was working fine yesterday but is dead today, the specific network provider you chose (e.g., Vodafone) might be experiencing a local mast outage.
- The Fix: Eliminate this single point of failure permanently by upgrading to an unsteered multi-network SIM from Anywhere SIM. If one mast goes down, the panel will automatically switch to EE, O2, or Three.
4. 2G/3G Network Sunsetting
Many older GSM alarm panels only operate on 2G or 3G frequencies. UK networks are actively shutting down these older networks (sunsetting) to make room for 5G.
- The Fix: Check your alarm hardware. You may need to upgrade the communicator module to a 4G-compatible unit, paired with a modern multi-network SIM, to ensure long-term functionality.