Nexus AUTOPILOT Installation And Operation Manual page 27

Course as set on Autopilot
instrument is different from
ship's steering compass.
NMEA does not engage,
NAV arrow does not come
on.
After some use, NAV
arrow does not come on.
Course under NAV steering
is erratic.
FAULT FINDING
If constant error, Autopilot
compass is not aligned with
for-aft line of boat.
Variable error in heading
caused by magnetic interfer-
ence.
Large errors not corrected by
above remedies or lack of
change in course set point
with different headings indi-
cate a defective compass.
Ships compass is not cor-
rect.
Compass: no reading or
wrong heading.
Irregular values.
NMEA receiver not installed
correctly.
No NMEA 0183 data re-
ceived.
Unreliable NMEA data de-
tected upon engagement.
No active waypoint.
Poor NMEA data detected.
Last "good" NMEA heading
is used until good data re-
stored.
May appear when close to
waypoint due to GPS-S/A.
error.
Compass heading informa-
tion is not consistent with
navigator.
Use Compass setting [C6] [ADJ] to adjust align-
ment of compass.
Verify that the steering compass is accurately cor-
rected and then correct the Autopilot compass as
per installation instructions.
1.
Run Auto-Deviation-Clear [C5] [CLR].
2.
Run Auto-Deviation [C3] [DEV]
3.
Recheck compass again.
Compensate ships compass.
Check that the local magnetic variation [C2] [VAR]
is set properly.
Check the Sea Damping [P2] [SEA].
Check receiver settings for proper output.
Check Nav cable for connection. to the correct
port.
Check connections and setup in transmitting in-
strument
Activate a waypoint.
Check for poor navigator installation causing bad
signal to noise ration. Check for erroneous data as
detected by navigator. Revert to magnetic course
only, if situation cannot be corrected.
Accept situation or revert to compass course
steering only.
Set heading in pilot i.e. true to true or magnetic to
magnetic so course is consistent with navigator.
Check NMEA wiring termination.
26