6. MAINTENANCE, TROUBLESHOOTING

6-4

6.6 Troubleshooting
The table below provides common symptoms of equipment troubles and the means to
rectify them.
Symptom Check, Remedy
Cannot turn on the power. • Check ship’s mains.
• Have a suitably qualified technician check the fuse in the
transceiver unit.
Bottom echo becomes
irregular.
• Rough seas. Distance to the bottom changes due to rolling
and pitching.
• Long range chosen. Transmission period is longer so ship’s
pitching and rolling are apt to affect detection of echo.
Weak echo • Output power set to minimum. Set to maximum, on the COM1
menu.
• Excessive TVG. Readjust TVG on the appropriate menu
(HORZ, VERT, ES). Note that readjustment of TVG is
necessary whenever the gain is adjusted.
Somewhat strange picture
color
• [BRILL] key setting too low. Increase brightness with [BRILL]
key.
Picture contains noise. • Equipment not grounded properly. Check equipment ground.
• Power cable is too close to the signal cable. Relocate power
cable or signal cable.
• Debris may be on sea surface. Reject unwanted noise with the
interference rejector on the COM1 menu.
Picture does not change
when tilt angle is changed.
(Bottom is not displayed in
vertical scan picture when
bottom is flat.)
• Problem in tilt mechanism or control line. Contact a FURUNO
agent or dealer for advice.