Owner's Manual
Page 99
... be spliced and connected to become turbulent. GPSMAP 392/398/492/498 Owner's Manual Mount the transducer cable cover well above the waterline. The transducer can cause cavitation that the transducer is below aluminum hull. DO NOT cut the transducer lead or any existing (Garmin or non-Garmin) transducer cables. Apply marine sealant to all screw threads to prevent water...
... be spliced and connected to become turbulent. GPSMAP 392/398/492/498 Owner's Manual Mount the transducer cable cover well above the waterline. The transducer can cause cavitation that the transducer is below aluminum hull. DO NOT cut the transducer lead or any existing (Garmin or non-Garmin) transducer cables. Apply marine sealant to all screw threads to prevent water...