Virtually all 406 MHz beacons incorporate a self-test mode of operation. Standard Self-Tests of beacons usually involve pressing a button or lifting a lever on the beacon and holding it for a few seconds. This usually results in the beacon flashing an LED or Strobe and/or creating an audible sound that indicates that the internal circuitry of the beacon is functioning correctly. You should always carefully follow the beacon manufacturer's instructions when carrying out a self-test as it is possible to get false results or inadvertently trigger a false alarm if perform the self-test incorrectly. If the beacon fails, then you should contact the beacon manufacturer or an appointed service agents for further advice and instructions.