Furuno Ls4100 manual Diagnostics, Troubleshooting table, Installation menu, Test display

3.6 Troubleshooting

The table below provides basic troubleshooting procedures which the user may follow to restore normal operation.

Troubleshooting table

If…		Then check …
neither echo nor	•	battery voltage.
fixed range scale	•	fuse.
appears	•	power cable.
no echo appears	•	if display advance
but the fixed		speed is set to “Stop.”
range scale	•	transducer plug
appears	•	transducer cable
echo appears but	•	if range shifting is set
no zero line		to “0.”
sensitivity is low	•	gain setting.
	• if air bubbles or marine
		life is clinging to the
		transducer face.
	•	if sediments are
		present in the water.
	• if the bottom is too soft
		to return an echo.
there is extreme	•	if the transducer is too
interference or		close to the engine.
noise	•	if the unit is properly
		grounded.
	• if other echo sounders
		of the same frequency
		as own are being
		operated nearby.
the speed/water	•	sensor plug.
temperature
readout is
unrealistic or not
present
the position	•	the connection
readout is		between sounder and
unrealistic or not		navigator.
present	•	navigator.

3.7 Diagnostics

If you feel your unit is not working properly, conduct the diagnostic test to find the problem. If you cannot restore normal operation, contact your dealer for advice.

1.Turn on the power while pressing the [MENU/ESC] key. Continue pressing the [MENU/ESC] key until the Installation menu appears.

Installation Menu

SIMULATION On

TEST ...

LCD PATTERN ...

MEMORY CLEAR

NMEA PORT	: In/Out
NMEA MIX	: Off
GPS WAAS*	: Off

SET BOTTOM LEVEL ..

*= Setting cannot be changed when NMEA PORT setting is "In/In."

Installation menu

2.Press▼ to choose TEST.

3.Press ► to start the test.

Level bar

	ROM	: OK
	RAM	: OK
	NMEA :
Water	Temp	:	68.2° F
Temperature,	Speed : 10.0km/h
Speed
Battery Voltage	Power :		12.4 V
Temperature	Body	:	39° C
inside display
unit	GPS (48502180**): OK
(Unit fixed at	Program No. 0252318-01.**
° C.)	Push [MENU] 3 times to exit.

** = Program version no.

Only when GP-310B is connected. (For GP-320B: 4850238**)

Test display

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