Each digital telephone endpoint (speakerphone) comes equipped with a backlit display,
which can be programmed to go into power saver after it has being idle for 60 seconds.
The backlit display is immediately activated whenever an action such as ringing,
going off hook or pressing any of the fixed or preprogrammed buttons, is taken.

If it's not working as stated above I would guess that the display is worn out. It happens.


Dean
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