190-01007-A1 System Maintenance Manual GTN 6XX/7XX Part 23 AML STCRev. 5 Page 5-95.3.1.1 COM Related AlertsTable 5-3. COM Alert Troubleshooting GuideAlert Text Possible Cause Corrective ActionCOM RADIO - COMradio needs service.A failure has been detected in the COMtransceiver. The transceiver may stillbe usable.This message may appear afteroperations in configuration mode.Cycle power to the entire GTN (bothGPS/NAV and COM circuit breakers)and see if the message has cleared.Contact Garmin technical support.REMOTE KEY STUCK- COM push-to-talk keyis stuck.The COM push-to-talk switch is stuckin the enabled or pressed state.Press the PTT switch to cycle itsoperation.If the message persists, contactGarmin technical support.Go to the GTN DIAGNOSTICS -DISCRETE INPUTS page inconfiguration mode and check that thestate of the input changes when thePTT switch is pressed and released.Verify that the PTT switch wiring iscorrect.REMOTE KEY STUCK- COM remote transferkey is stuck.The COM remote transfer key is stuckin the enabled or pressed state.Go to the GTN DIAGNOSTICS -DISCRETE INPUTS page inconfiguration mode and check that thestate of the input changes when theCOM remote frequency incrementswitch is pressed and released.Verify that the COM remote frequencyincrement switch wiring is correct.Press the COM remote transfer switchto cycle its operation.If the problem persists, contactGarmin technical support.
