Yealink SIP-T54S Administrator's Manual page 201

Phone User Interface:
None
phone_setting.hold_and_held_power_led_flash_enable
Description:
Enables or disables the power indicator LED to flash when a call is placed on hold or is held.
For SIP-
T54S/T52S/T48G/T48S/T46G/T46S/T42G/T42S/T41P/T41S/T40P/T40G/T29G/T27P/T
27G/T23P/T23G/T21(P) E2 IP phones:
0-Disabled (power indicator LED does not flash)
1-Enabled ( power indicator LED fast flashes (500ms) red)
For SIP-T19(P) E2 IP phones:
0-Disabled (power indicator LED does not flash)
1-Enabled ( power indicator LED fast flashes (500ms) yellow)
Note: It is not applicable to CP860/CP920 IP phones.
Web User Interface:
Features->Power LED->Hold/Held Power Light Flash
Phone User Interface:
None
phone_setting.talk_and_dial_power_led_enable
Description:
Enables or disables the power indicator LED to be turned on when the IP phone is busy.
For SIP-
T54S/T52S/T48G/T48S/T46G/T46S/T42G/T42S/T41P/T41S/T40P/T40G/T29G/T27P/T
27G/T23P/T23G/T21(P) E2 IP phones:
0-Disabled (power indicator LED is off)
1-Enabled (power indicator LED is solid red)
For SIP-T19(P) E2 IP phones:
0-Disabled (power indicator LED is off)
1-Enabled (power indicator LED is solid yellow)
Note: It is not applicable to CP860/CP920 IP phones.
Web User Interface:
Features->Power LED->Talk/Dial Power Light On
Phone User Interface:
Parameters
Configuring Basic Features
Permitted
Default
Values
0 or 1 0
0 or 1 0
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