Panasonic KX-T336 System Reference Manual page 1358

3) Testing the DN button indicators for lighting in red.
4) Testing the DN button indicators for flashing in red.
5) Testing the indicators of the MESSAGE, CONF, FWD/DND,
AUTO DIAL/STORE, AUTO ANSWER/MUTE, SP-PHONE
buttons for lighting in red.
CONF button
FWD/DND
button
LED TEST
LED TEST
LED TEST
12-C-31
(70695)
DN buttons
DN buttons
MESSAGE button
AUTO DIAL/
STORE button
AUTO ANSWER/
MUTE button
SP-PHONE button