How to Install a Garmin GNC 300XL
- 1). Check that all parts and information are available in your Garmin package. This includes the GNC 300XL Unit and NavData card, GPS antenna, installation rack and connectors, Pilot's Guide, Quick Reference Guide, Database Subscription packet and Warrant Registration card.
- 2). Insert a 3/32" Allen wrench in the small hole adjacent to the dual knob.
- 3). Rotate the wrench counterclockwise until it stops to ensure the pawl latch is in the proper position.
- 4). Insert the GNC 300XL into the aviation rack and rotate the wrench clockwise to secure the unit. Press gently on the left side of the unit while tightening to make sure the connectors fit together properly.
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