Garmin GNC 255 Installation Manual - page 55
190-01182-02
GTR 225/GNC 255 TSO Installation Manual
Rev. B
Page 6-1
6 POST INSTALLATION CONFIGURATION AND CHECKOUT
PROCEDURES
6.1 System Configuration Overview
This section contains instructions for configuring the GTR/GNC for each installation as well as checks to
ensure the system is properly installed and functioning correctly. A summary of the steps required for
configuration and checkout of the GTR/GNC is as follows:
Perform the installation checks (Section 6.5)
Configure the GTR/GNC for the specific installation (Section 6.4)
Perform ground checks to verify the interfaces to external sensors (Section 6.6)
Perform the specified flight checks (Section 6.7)
Update the aircraft documentation (Section 6.9)
6.2 Mounting, Wiring, and Power Checks
Verify that all cables are properly secured and shields are connected to the shield block of the connectors.
Check the movement of the flight and engine controls to verify there is no interference between the cabling
and control systems. Ensure that all wiring is installed as described in Section 3.4.
Prior to powering up the GTR/GNC, the wiring harness must be checked for proper connections to the
aircraft systems and other avionics equipment. Point to point continuity must be checked to expose any
faults such as shorting to ground. Any faults or discrepancies must be corrected before proceeding.
After accomplishing a continuity check, perform power and ground checks to verify proper power
distribution to the GTR/GNC. Any faults or discrepancies should be corrected at this time. Remove power
from the aircraft upon completion of the harness checkout.
The GTR/GNC can be installed after completion of the continuity and power checks. The GTR/GNC
should be installed into the rack and secured appropriately, as described in Section 4.7.1. The GTR/GNC
must be connected to the wiring harness and antennas.
CAUTION
When 14 VDC or 28 VDC lighting buses are connected to the GTR/GNC, connection of
the aircraft lighting bus to the incorrect input pins can cause damage to the GTR/GNC.
Always start this test with the dimming bus at the lowest setting, and slowly increase the
brightness. If it is noticed that the lighting level on the GTR/GNC does not increase as the
lighting bus input is increased in brightness, verify that the wiring is correct before
proceeding.