Is there any way to change the intensity of LCD backlight on the EXP40?
You can adjust the backlight on LCD screen of the EXP40 expansion module via the host phone. The backlight on the LCD screen of the EXP40 expansion module is synchronized with that of the host phone.
To adjust the backlight on the LCD screen of the EXP40 expansion module connected to
the host phone (Taking the SIP-T46S IP phone as an example for reference):
1. Press Menu->Basic->Display->Backlight on the host phone.
2. Select the desired value for Active Level, Inactive Level and Backlight Time. If Backlight Time is selected as 30s and keep inactive for 30s, then phone will turn to “Low” level and the EXP40 will turn to “Low” level at the same time.
For firmware V80 or above, the backlight level of EXP40 will keep synchronization with host phone.
For firmware which older than V80, if select the Active Level as “1” or “2”, the host phone backlight will get progressively dimmer but EXP40 turns the backlight off completely. If select the Active Level as other values, it will keep synchronization with host phone.
For more information on adjusting the backlight on the phone, refer to the Backlight section of
Yealink phone-specific user guide, available online: