Japan Radio Co. JLN-740A, Instruction Manual

Page: 153 / 232

10-3 Chapter 10 Maintenance and Inspection
10
10.4 Troubleshooting
Fault symptom
JLN-
740A
JLN-
740N
JLN-
741A
JLN-
741N
Assumed cause Countermeasure
The power supply is
not turned on even if
the power switch is
pressed.
   
Power is not supplied
from the on-board
distribution board.
Check if the wiring
from the distribution
board is normal.
Check that the
distribution board
circuit breaker is ON.
   
The fuse that is
connected to the
power cable has been
blown.
After checking that the
wiring is normal,
replace the fuse.
   
The display switch is
faulty.
Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
No screen is
displayed on the LCD
unit.
   
The screen brightness
of the LCD unit is set
too low.
Adjust the brightness.
(Refer to 3.1.2, 5.1.2,
and 7.1.1.)
   
The LCD unit is faulty. Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
Ship speed is not
displayed.
   
The model setting is
incorrect.
Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
The sensitivity of the
touch panel is low.
 
The touch position is
shifted.
Modify the touch
position. (Refer to
4.1.3.1.)
 
The LCD unit is faulty. Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
Alert, “NO BUBBLE
REFERENCE”, is
displayed.
 
Bubble detection
reference data is not
set.
Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
“NO BUBBLE” alert is
displayed.
 
Bubble detection
reference data is not
set.
Contact JRC Sales
Department, or your
nearest branch, sales
office, or our
distributor.
Missing data
   
The water depth is too
low.
Since a ship speed
cannot be measured
when the water depth
is lower than 3 m,
check the water depth.