Garmin GTN 6 series Maintenance Manual - page 69

190-01007-A1

System Maintenance Manual GTN 6XX/7XX Part 23 AML STC

Rev. 6

Page 6-1

6 EQUIPMENT REMOVAL AND REINSTALLATION

This section describes how to remove and replace equipment associated with this STC. After removal and 

reinstallation, LRUs must be configured and tested as described in Section 7.

CAUTION

When removing and/or replacing a GTN, GMA 35, or any other item under the scope of 

the STC installation, always ensure that the aircraft power is off. Unplug any auxiliary 

power supply.

6.1 GTN 

Removal

1. Locate and pull the GTN GPS/NAV and COM (635/650/750 only) circuit breakers. 

2. Locate the unit retention mechanism access hole at the bottom left corner of the unit face.

3. Insert a 3/32-inch hex tool into the access hole and rotate the fastener counterclockwise until the 

unit is forced out about 3/8 inch and can be freely pulled from the rack.

4. Slide the GTN unit out of the rack.

Reinstallation

1. Ensure that the GTN GPS/NAV and COM circuit breakers are pulled.

2. Slide the GTN straight into the rack until it stops about 1 inch short of the fully seated position.

3. Insert a 3/32-inch hex drive into the unit retention mechanism access hole at the bottom of the unit 

face and rotate the tool clockwise while pressing the bezel until the unit is firmly seated in the 

rack.

4. Once the GTN is reinstalled, verify that the unit power-up self test sequence is successfully 

completed and no failure messages or configuration error messages are annunciated. Section 6.1.1 

outlines the power-up self-test sequence.

NOTE

It may be necessary to insert the hex drive tool into the access hole and rotate the cam 

mechanism 90 degrees counterclockwise to ensure correct position prior to placing the 

unit in the rack.

CAUTION

Be sure not to over-tighten the unit into the rack. The application of hex drive tool torque 

exceeding 15 in-lbs can damage the locking mechanism.