Gtn - Garmin GTN 6 Series Maintenance Manual

5.1 GTN

Removal
1. Remove power from the GTN.
Bell and MD Helicopter Models: To remove power, pull all GTN circuit breakers.
Eurocopter Models: Power is removed for units located in the console by switching off the
avionics master relay. For units located in the instrument panel, power is removed by switching off
the GPS 1 or GPS/COM 1 switch.
2. Locate the unit retention mechanism access hole at the bottom-left corner of the unit face.
3. Insert a 3/32" hex tool into the access hole and turn the fastener counterclockwise until the unit is
forced out about 3/8 inches and can be freely pulled from the rack.
4. Slide the GTN unit out of the rack.
Replacement
CAUTION
Be sure not to overtighten the unit into the rack. The application of hex drive tool torque
exceeding 15 in-lbf can damage the locking mechanism.
NOTE
It may be necessary to insert the hex drive tool into the access hole and turn the cam
mechanism 90° counterclockwise to ensure correct position prior to placing the unit in the
rack.
CAUTION
The Bluetooth antenna port on the GMA 35c has a tight clearance between the GMA and
GTN. Ensure the GMA and antenna cable are fully seated before inserting the GTN. The
face of the GMA 35c should be flush with the mounting rack when fully seated.
1. Ensure that no power is being supplied to the GTN.
2. Slide the GTN straight into the rack until it stops about 1.0 inch short of the fully-seated position.
3. Insert a 3/32" hex drive into the unit retention mechanism access hole at the bottom of the unit face
and turn the tool clockwise while pressing the bezel until the unit is firmly seated in the rack.
4. Verify the unit power-up self-test sequence is successfully completed.
5. Verify there are no failure messages or configuration error messages annunciated. Refer to
Section 5.1.1.
190-01007-B1
Rev. 4
GTN 6XX/7XX Part 27 AML STC Maintenance Manual
Page 5-2