Humminbird PiranhaMAX 155 Installation And Operation Manual page 60

2. There is no transducer detected.
The PiranhaMAX has the ability to detect and identify that a transducer
is connected. When powering on, if a message indicates "transducer not
connected", make sure that an appropriate transducer connector is plugged
into the unit. In addition, inspect the transducer cable from end to end for
breaks, kinks, or cuts in the outer casing of the cable. Also make sure that
the transducer is fully submerged in water. If the transducer is connected
to the unit through a switch, temporarily connect it directly to the unit and
try again. If none of these actions identifies an obvious problem, the
transducer itself is probably at fault. Be sure to include the transducer if
returning the unit for repair.
3. There is no bottom reading visible on the display.
If the loss of bottom information occurs only at high boat speeds, the
transducer needs adjusting – see your PiranhaMAX Installation Guide for
details. Also, in very deep water, it may be necessary to increase the
sensitivity setting manually to maintain a graphic depiction of the bottom. If
you are using a transducer switch to connect two transducers to the
PiranhaMAX, make sure that the switch is in the correct position to connect a
transducer that is in the water. (If a trolling motor transducer is selected and the
trolling motor is out of the water, no sonar information appears.) If none of these
actions solves the problem, inspect the transducer cable from end to end for
breaks, kinks, or cuts in the outer casing of the cable. If the transducer is
connected to the unit through a switch, temporarily connect it directly to the unit
and try again. If none of these actions identifies an obvious problem, the
transducer itself may be at fault. Be sure to include the transducer if returning
the unit for repair.
4. When in very shallow water, I get gaps in the bottom reading and
inconsistent digital depth indication.
The PiranhaMAX will work reliably in water 3 feet (90 cm) or deeper.
Remember that the depth is measured from the transducer, not from the
surface of the water.
Troubleshooting
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