Furuno GP-1850WF - Manual (Page 97)

13. MAINTENANCE & TROUBLESHOOTING
13-3
Simple troubleshooting (sounder)
If … Then …
check if picture advance speed is set to “STOP”
on the SOUNDER SETUP OPTIONS menu.
no picture but markers and characters appear
check for loosened transducer connector.
picture appears but no zero line
if using manual video sounder operation, range
is shifted; set shifting zero to correct.
check gain setting, if using manual operation.
marine life or air bubbles may be clinging to
transducer face.
water may be dirty.
picture sensitivity is too low
bottom may be too soft to return a suitable echo.
depth is not displayed
adjust echo offset on the SOUNDER SETUP
OPTIONS menu (SYSTEM SETUP soft key).
check if transducer cable is near ship’s engine. If
it is, relocate it.
check ground. noise or interference obstructs the display
other video sounders may be operating nearby
and on same frequency.
water temperature graph appears but no or
wrong readout
check for loosened sensor cable.
13.4 Error Messages
The GP-1850WF/1850WDF displays the
following error messages on the alarm menu
to alert you to possible trouble.
Error messages
Error Message Meaning, remedy
NO GPS FIX No GPS signal. Check
antenna cable.
NO DIFFERENTIAL
GPS CORRECTION.
(GP-1850WDF only) No DGPS signal.
Check antenna.
VOLTAGE OF
INTERNAL BATTERY
IS LOW. Voltage of internal
battery is low.
Request replacement
of battery.