Can’t Read Voltages That Low, Limited to Bottom of Range—the battery‑alarm screen voltage value is lower than the voltage at which the Fishfinder 300C automatically turns off.
Deep-WaterAlarm—the deep-water alarm depth (Configure > Alarms > Deep Water > On) has been reached.
Drift Alarm—the depth has changed by the amount on the drift-alarm screen (Configure
>Alarms > Drift > On).
Entering (Leaving) Target Water Temperature—the target water temperature is 2°F (1.1°C) above or below the water temperature alarm (Configure > Alarms > Water Temp > On). These messages appear when you enter or leave that zone.
Fish Alarm—an icon appears (page 12) and a beep sounds (if enabled) when a fish is detected. This alarm does not show a message banner.
Shallow-WaterAlarm—the shallow‑water alarm depth (Configure > Alarms > Shallow Water > On) has been reached.
Simulating Operation—the Fishfinder
300C is in simulator mode.
Sonar Disabled Due to High Voltage. Please Check Unit Voltage—the Fishfinder 300C voltage is greater than 20 volts. Check the battery voltage (Configure > Numbers). Turn the Fishfinder 300C off and back on
again to restore the sonar.
Sonar Failed, Unit Needs Repair—there
is an internal problem with the Fishfinder
300C. Contact your dealer or Garmin
Product Support to have the Fishfinder 300C
serviced.
Transducer Disconnected, Sonar Turned Off—the transducer or cable are not attached or need repair. If the transducer cable is removed while the Fishfinder 300C is on, reconnect and cycle power.
Water Speed Sensor Is Not Working—the speed sensor is not detected. Check the connections.