Brother MFC640CW Service Manual page 218

If the sensing status are as listed below, the LCD will show "DFDRCVRS P1
"IKIYICIMVTHK ," which can be switched by pressing the Black Start (Mono Start) key.
Given below is the relationship between the LCD indication, sensor name and sensor status.
LCD
DF Document front sensor
DR Document rear sensor
CV Scanner open sensor
RS Registration sensor
P1 Purge cam switch
IK Black ink cartridge sensor
IY Yellow ink cartridge sensor
IC Cyan ink cartridge sensor
IM Magenta ink cartridge sensor
VT Head driver chip temperature sensor
HK Hook switch*
The HK is displayed even on those models not equipped with their related sensors.
(2) Change the detecting conditions (e.g., open the scanner unit or insert paper through the
registration sensor or remove the ink cartridges), and then check that the indication on the LCD
changes according to the sensor states.
(3) To stop this operation and return the machine to the initial stage of the maintenance mode,
press the Stop/Exit key.
Sensors
8 - 2 0
Sensing status
No document detected.
No document detected.
Scanner unit closed.
No recording paper detected.
Purge cam switch ON.
Black ink cartridge loaded (Black ink present).
Yellow ink cartridge loaded (Yellow ink present).
Cyan ink cartridge loaded (Cyan ink present).
Magenta ink cartridge loaded (Magenta ink present).
Driver chip temperature within the allowable range.
On-hook state.
" and
* MFC640CW
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