8.1 General
Before you contact your Nexus dealer and to assist your dealer to give you a better
service, please check the following points and make a list of:
• All connected instrument and transducers, including their software versions.
• Nexus Network ID numbers for each instrument (displayed at power up).
In most cases, the reason for faults in electronic equipment is poor installation.
Therefore, always first check that:
• Installation and connection is made per instructions for instruments and
transducers.
• Screw terminals are carefully tightened.
• No corrosion on any connection points.
• No loose ends in the wires, causing short cuts to adjacent wires.
• Cables for damage and that none are squeezed or worn.
• Battery voltage is sufficient, should be at least 11 V DC.
• The fuse is not blown and that the circuit-breaker has not opened.
• The fuse is of the right type.
• Two instruments do not have the same ID number.
8.2 Symptom - Cause - Action
In the table below, causes marked [ * ] are more likely to occur during installation or
when rewiring has taken place.
Symptom Cause Action
Autopilot turns off * Voltage below
minimum. Make sure 12/24 V is applied to battery
terminals at Servo Unit.
Autopilot does not
turn on * Voltage not
applied. Make sure 12/24 V is applied to battery
terminals at Servo Unit.
* Voltage polarity is
reversed. Make sure + and - is applied to correct
terminals
* Boats safety switch
is open. Close the safety switch.
* Fuse burned out. Check and replace fuse as necessary,
located in the Servo Unit.
Autopilot turns on,
but the pumpset
does not run
Slow blow (high
current) fuse in
Servo Unit is blown.
Replace fuse. If fuse regularly blows,
check for excessive rudder load or
mechanical defects in steering system
Pumpset drive
section in Servo Unit
may have failed to
open.
Replace transistors, integrated circuits
or entire circuit board.
Pumpset motor turns
but the rudder does not
move
Broken or loose motor
coupling. Replace or tighten coupling as necessary.
33