NorthStar EXPLORER 443D Installation And Operation Manual page 36

2. The fishfinder won't turn off:
The fishfinder may have been wired for Auto
power. In this case, the fishfinder cannot be
turned off while the ignition power is on.
(See Auto power wiring in section 6-5 Wiring
options.)
3. The fishfinder operates erratically:
a) Check that the transducer does not have
debris (e.g. weed, plastic bag) caught around
it.
b) The transducer may have been damaged
during launching, running aground or while
underway with debris etc. If the transducer
has been impacted, it may have been kicked
up on the bracket. If it is not physically
damaged, reset the transducer back to its
original position. (See the Transom Transducer
Installation Guide.)
c) When the transducer is less that 2 ft. (0.6 m)
from the bottom, the depth readings may
become inconsistent and erratic.
d) Manual Gain may be set too low, which may
cause weak bottom echo or no fish signals. If
in Manual Gain, try increasing the Gain.
e) Ensure the back of the bottom surface of the
transducer is slightly lower than the front and
the front is as deep in the water as possible
in order to minimize the generation of
bubbles through cavitation. (See the Transom
Transducers Installation Guide.)
f) Check the transducer and power cable
connectors at the back of the display unit
are securely plugged in and the collars are
locked in place. The collars must be secure for
watertight connection.
g) Inspect the power cable from end to end for
damage such as cuts, breaks, squashed or
trapped sections.
h) Ensure there is not another fishfinder or
depth sounder turned on, which may
interfere with this fishfinder.
36 Northstar Explorer 443d/443df Installation and Operation Manual
i) Electrical noise from the boat's engine or
an accessory may be interfering with the
transducer(s) and/or the Northstar fishfinder.
This may cause the fishfinder to automatically
decrease the Gain unless using Manual Gain.
The fishfinder thus eliminates weaker signals
such as fish or even the bottom from the
display. This may be checked by switching
off other instruments, accessories (e.g. bilge
pump) and the motor until the offending
device is located. To stop problems from
electrical noise, try:
- re-routing the power and transducer
cable(s) away from the boat's other
electrical wiring.
- routing the display unit's power cable
directly to the battery with an in-line fuse.
4. Bottom is not displayed:
a) The fishfinder may have Manual Range
selected and the depth may be outside the
range value selected. Either change the
fishfinder to Auto Range or select another
depth range (see section 4-5 Range).
b) The depth may be outside the fishfinder's
range. While in Auto Range, the display unit
will display "--.-" to indicate that there is no
bottom detected. A display of the bottom
should reappear when in shallower water.
5. The bottom is displayed too far up
the screen:
The fishfinder may have Manual Range
selected and the selected Range value is
too high for the depth. Either change the
fishfinder to Auto Range or select another
depth range (see section 4-5 Range).
6. Bottom echo disappears or erratic
digital reading while the boat is moving:
a) Ensure the back of the bottom surface of the
transducer is slightly lower than the front and
the front is as deep in the water as possible
in order to minimise the generation of
bubbles through cavitation. (See the Transom
Transducers Installation Guide, for more
information.)