Eventide ARGUS 5000 - Page 199

This screen message indicates that no data is being received over the data link. Besides
the obvious reason (GPS turned OFF), additional possibilities are that the receiver
output isn't setup properly, or there is a wiring error. The Argus input is optically
coupled, and it is vital that the two pins shown in our installation drawing be
connected. Do NOT rely on aircraft ground for a signal return; our input is not
grounded and it won't work. If you see this message and everything does seem to be
connected correctly, attach an oscilloscope probe between pins 16 and 4 on the Argus
(at the Argus tray connector) and visually verify that the data signal is present across
those pins. It is very unlikely that the Argus input is defective, as this is obviously vital
to its operation and is checked most carefully.
LRN COMM FAULT Message
— BRG TK — KT5
.- NM —: — :--
LRN COMM
FAULT
[inioiini ^te
—MSL PLAN/720
This message indicates that there is a communications
failure between the Argus and the navigation receiver.
The most likely problem is incorrect parity or baud rate.
When you select a GPS on the setup page, these data
communication parameters are automatically defaulted to
the values that the receivers are shipped with. However,
most nav receivers have adjustable parameters and these
could have been changed, deliberately or accidentally, by
the factory, previous owner, etc. It is frequently
necessary to change the receiver parameters when using
a fuel flow display or ELT that cannot itself be adjusted.
If this has been done, the Argus defaults may be
incorrect. Regardless of the cause of the error, all
devices on the data bus must have the same settings. The Argus settings are adjustable
as described earlier in this section; the receiver settings may be adjusted as described
in the associated manual. Other possible causes of this message include reversed data
lines or poor signal levels. It is not always possible for the Argus to distinguish an RS-
232 error from one caused by the GPS sending invalid data (see below).
WRONG LRN SELECTED Message
July 1999 Argus 5000/7000 Ver. 5.xx Reference Manual Part#141003 195