Garmin GPS 400W Installation Manual page 130

Problem
OBS Resolver won't
calibrate.
OBS indication on
400W Series unit
does not agree with
OBS setting.
400W Series unit is
not receiving
heading from
compass system
(ARINC 429
heading input used)
Autopilot is not
getting GPSS/Roll
Steering data from
the 400W Series
unit (ARINC 429
Roll Steering used)
RMI pointer does
not indicate correctly
Tuning data not
updating DME
ARINC 429 device
is not receiving data
from the 400W
Series unit.
Page 6-2
Rev. G
Table 6-1. Troubleshooting Guide
Possible Cause
Incompatible resolver or
improper connection.
400W Series unit resolver input
not calibrated correctly.
Resolver has not been
calibrated.
ARINC 429 input port speed
not correct
Wiring connections are
incorrect.
400W Series unit does not
have a position or flight plan
entered.
400W Series unit ARINC 429
output not configured correctly.
ARINC 429 output port speed
not correct.
Wiring connections are
incorrect.
Certain autopilots require
groundspeed for GPSS to be
enabled.
Desired RMI source has not
been selected.
Wiring connections are
incorrect.
Incorrect configuration.
Wiring connections are
incorrect.
400W Series unit ARINC 429
output not configured correctly.
ARINC 429 input port speed
not correct
Wiring connections are
incorrect.
Solution
Check the resolver specifications and
wiring.
Check wiring and calibration.
Check ARINC 429 input port speed
setting for port that device is
connected to and verify that the
speed is correct for that device.
Check wiring.
Acquire GPS position and enter a
flight plan.
Check ARINC 429 output port setting
for port that autopilot is connected to.
Check ARINC 429 output port speed
setting for port that autopilot is
connected to and verify that the
speed is correct for autopilot.
Check wiring. Must be connected to
main GPS 429 output.
Ensure that groundspeed is provided
if required by the autopilot.
Check the OBI source selection on
the Main CDI/OBS Config page.
Check wiring.
Check the DME Channel Mode on
the VOR/LOC/GS CDI page.
Check wiring.
Check ARINC 429 output port setting
for port that device is connected to.
Check ARINC 429 input port speed
setting for port that device is
connected to and verify that the
speed is correct for that device.
Check wiring.
400W Series Installation Manual
190-00356-02