Garmin GIA 64 units purchased or installed since October 2021 listed in the link below are affected.
One or both GIA 64 units may experience a total loss of COM when aircraft power input voltage is in the range of 5-7 VDC. This condition may be encountered temporarily during engine start and/or aircraft power bus switching.
Total loss of COM will persist until the affected GIA 64 units are power cycled.
This service bulletin contains instructions to return the affected product to Garmin.
This Service Bulletin is warranty reimbursable with a deadline of May 31, 2022 after which this upgrade will no longer be reimbursable for labor.