At firealarm.com, we often see the trouble light on the Gamewell-FCI ATD-L3R-IV indicate various issues. First, check the display for any specific error codes or messages. If none are present, start by verifying power and connections. Ensure that the power source is functioning correctly and that all wiring connections are secure. If power and connections seem fine, try resetting the device by power cycling it. If the trouble light persists after these steps, consult the device’s manual for further troubleshooting steps or consider contacting a certified technician for assistance.