190-01007-01
GTN 725/750 Maintenance Manual
Rev. 5
Page 5-2
5.1 GTN 725/750 Unit Removal and Replacement
Refer to figure 5-1 while performing the following procedure.
Removal
1. Pull the GTN main, COM, and NAV circuit breakers. Refer to individual aircraft installation
documentation to determine circuit breaker locations.
2. Insert a 3/32" hex drive tool into the unit retention mechanism access hole at the bottom left-hand
corner of the display head bezel. Refer to figure 5-1 for details. Turn the hex tool counterclockwise
until the unit is forced out approximately 3/8" and the hex drive tool completely stops. This takes
approximately 17.5 turns of the hex tool.
3. Slide the GTN unit out of the rack.
Replacement
1. Check GTN main, COM, and NAV circuit breakers are pulled.
2. Slide the GTN straight into the rack until it stops about 3/8" short of the fully seated position.
3. Insert a 3/32" hex drive tool into the unit retention access hole at the bottom of the unit face. Turn
the hex tool clockwise while pressing the left side of the bezel until the unit is firmly seated in the
rack.
Figure 5-1 GTN 725/750 Unit Retention Mechanism Adjustment
UNIT RETENTION MECHANISM
ACCESS HOLE
