My Garmin 4000 Depth Measurement Stopped Working

Starting on January 26, 2026, my Garmin 4000 device has been continuously displaying a "Cannot receive transmission data" warning and failing to measure depth. The issue does not clear up under any circumstances, rendering the device completely unusable.

I cannot recall which dealer or store I originally purchased the device from, so I have not been able to apply to them directly, nor have I contacted Garmin authorized service or customer support yet.

I request that the root cause of this defect in my Garmin 4000 device be diagnosed, that all necessary repairs be performed, and that all functions—including depth measurement—be restored to full working order.