Panasonic KX-FLB852CX Service Manual page 249

7.12.19. OPTION CASSETTE COVER SENSOR
This switch detects whether the side cover of option cassette is opened or not.
When the side cover is opened, the signal of IC600-P17pin becomes high level.
When the side cover is closed and the option paper tray is set, the signal of IC600-P17pin becomes low level.
7.12.20. OPTION CASSETTE PAPER SENSOR
This switch detects whether there are recording papers in the paper tray #3.
When there are recording papers in the tray, the input signal of IC600-R16pin becomes high level.
When there are no recording papers in the tray, the input signal of IC600-R16pin becomes low level.
Signal (IC600-P17pin)
Cover open
Cover close and tray set
Signal (IC600-R16pin)
Recording paper exist
No recording paper
249
High level
Low level
High level
Low level
KX-FLB852CX / KX-FLB852CXS