Furuno 851 MARK-2 - Manual (Page 39)

4-2
4.2 Replacing the Fuse
The fuse in the power cable protects the
equipment against reverse polarity of ship’s
mains, overcurrent, and equipment fault. If
the fuse blows, find the cause before
replacing it. Never use an incorrect fuse–
serious damage to equipment may result
and void the warranty.
24/32 VDC :5 A fuse
12 VDC :10 A fuse
4.3 Troubleshooting
Table 4-2 contains simple troubleshooting
procedures which you can follow to try to
restore normal operation. If you cannot
restore normal operation, do not attempt to
check inside any unit of the radar system.
Any repair work is best left to a qualified
technician.
Table 4-2 Troubleshooting table
If...
you pressed the
[POWER] key to
turn on the radar
the radar has
warmed up and you
pressed the
[ST-BYTX] key to
transmit
you have adjusted
the gain with FTC
and STC off
a key is pressed
But...
the control panel does not
light
nothing appears on the
display or display contrast
is poor
characters are distorted
the antenna does not
rotate
characters and indications
are abnormal
neither noise nor targets
appear (indications and
markers do)
neither indications nor
markers appear
(noise and targets do)
the sweep (radial line
sweeping around the
display) is not
synchronized with
antenna rotation
there is no change in
sensitivity.
nothing happens
Then...
try adjusting the control panel backlighting
on the Brilliance/Backlighting menu.
battery may have discharged.
check fuse in power cable.
try adjusting the tone.
(Extreme ambient temperature may affect
display tone.)
request service.
the problem may be in antenna unit.
Request service.
have a qualified technician check the set.
check signal cable for damage.
check signal cable for damage.
the problem may be in the antenna unit.
Request service.
request service.
key may be faulty. Request service.