Panasonic KX-TD500 System Reference Manual page 973

Conditions
Held Call Reminder
Held Call Reminder (ATT)
Function
The following functions appear on the function line of this setting screen.
1 COMMON 2
COMMON (SHOW LV, CHG LV, INS, OUS, REMOVE, EXIT) and HRD CPY keys
are available in this setting screen.
For operation, refer to Section 8-I "Operation of Function Keys".
If these items are programmed however "System-Operation" Held Call
Reminder is not set to "Yes", Held Call Reminder does not function.
3 4 5 6 HRD CPY 7
10-D-23
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