Garmin G500 Pilot's Manual page 335

NOTE: The LOCK soft key on the XM Information Page (Auxiliary Page
Group) is used to save GDL 69A activation data when the Sirius XM
Satellite Radio services are initially set up. It is not used during normal
Sirius XM Satellite Radio operation, but there should be no adverse effects
if inadvertently selected during flight. Refer to the GDL 69/69A Sirius XM
Satellite Radio Activation Instructions (190-00355-04, Rev G, or later) for
further information.
If XM WX Satellite weather services have not been activated, the weather
product names will be displayed in gray (see below) on the XM Information
Page and a yellow Activation Required message is displayed in the center of
the Weather Data Link Page (Map Page Group). The Service Class refers to the
groupings of weather products available for subscription.
190-00601-02 Rev. J Garmin G500/G600 Pilot's Guide
TOC Cover
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