Basic troubleshooting that should help you with the most common troubles. Most of the cases that require attention occur during startup (and setup) of the GSM module.


GSM module status is reported by this LED.

  • ON: Normal operation, GSM successfully initialized.

  • Flashing slow: 1s on, 0.2s off - GSM module did not responded.

  • Flashing fast: 0.2s on, 0.2s off - incorrect/unrecognized GSM module response.

  • OFF: Failure, alarm didn’t start at all

Check that the battery is charged (for at least 1 hour), then disconnect the USB power cable, press the Standby/Reset Button, wait for about a minute and then press the Start Button. This will ensure a complete restart; if problems persist, contact support.


LED2 indicates the status of the SIM card and GSM network registration.

  • ON: Normal operation. SIM functioning as expected, GSM registered.

  • Flashing fast: 0.2s on, 0.2s off - SIM failure. Check SIM.

    • Possible reasons: the SIM is incorrectly/incompletely seated, or bad. 

    • Check for proper function of the SIM in another phone, and verify correct SIM insertion into the connector.

  • OFF: No GSM connection

    • GSM network unavailable (check signal strength in your area) or

    • SIM is PIN protected. Disable any PIN on the SIM.

Test the SIM on your phone to ensure it is able to register onto the GSM network.

Depending on your region and operator, there could be some additional steps required before using the SIM (i.e. activation).

SMS Sending Error Indicator

If you provide a bad telephone number (i.e. non-existing), the alarm will try to send an SMS to this number, which will (of course) fail. The function of sending SMS messages also has a built-in timer; even if it looks stuck, the alarm will move on to the next telephone number once the timeout elapses. If the alarm cannot send an SMS, it will turn on LED 3 to show that there was error. Note: if the LEDs are disabled to save power, LED 3 will remain off. LED 3 will go off once any SMS is properly sent. There are many reasons why sending an SMS can fail, from bad QOS (weak signal) to insufficient credit on SIM card.

  • You, as the operator, are responsible for maintaining credit on the SIM card. There is no global standard to determine credit status, so we can’t check it for you.


SMS status indicator

  • OFF: Normal

  • On: The last SMS attempt failed (bad number?).

Verify the numbers programmed into the alarm if this LED ever lights up.


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