Toyota Lexusc Owner's Handbook Manual page 612

IN CASE OF AN EMERGENCY
NOTICE
If your vehicle is in area where the GPS signal is weak
or cannot be received the Lexus Link System, the color
of the indicator light will change from green to amber.
The system is not operated. This system is only
operational in GPS and analog cellular coverage areas.
Upon subscription expiration, all Lexus Link services
(i.e. automatic notification, emergency call functions,
service call functions, door locking/unlocking function)
are deactivated.
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