Chapter 8 - Troubleshooting 490 Operations
Page 8-2
490 Echo Sounder Operations Manual Rev. B2
Troubleshooting the echo sounder
Figure 8: Troubleshooting the echo sounder (961/962)
No echoes displayed when
STAR
key is pressed.
Is the
961/962
software
Version 3.0 or
greater?
Has
NMEA Port 3
been configured
for the 490?
Check
the 490's STAT
indicator
What
is the flash
rate of the STAT
indicator?
Is the
Advance
Speed set to
zero?
YES
YES
YES
NO
NO
NO
OFF
STEADY
ON
FLASHING
ONCE
PER
SECOND
FOUR
TIMES
PER
SECOND
Contact Northstar Service to
upgrade to the latest version
of 961/962 software.
Change the Advance Speed
setting.
Configure NMEA Port 3 for
the 490. See the
490
Operations Manual
(GM490)
for instructions.
1. Check fuses and circuit
breakers
2. Check power to 490 with
a voltmeter.
3. Verify that the data cable
between the 961/962 and
the 490 is properly wired
and connected.
1. Check transducer
connector for the
proper wiring.
2. If wiring is correct,check
transducer impedance
with an ohmmeter.
3. If the transducer is open
or shorted, replace it
There's a hardware problem
with the 490.
The 490 and the 961/961
aren't communicating properly.
Check the wiring of the data
cable between the 961/962
and the 490.