Brother MFC9700 - Sensors and Actuators

III - 10
2.3 Sensors and Actuators
This machine has 13 sensors: 10 photosensors*, two thermistors, and a mechanical switch as
described below.
(*Models supporting a 2nd paper cassette have two more photosensors--2nd registration sensor and 2nd
cassette sensor.)
Sensor name Type Located on
Document front sensor Photosensor Document sensor PCB
Document rear sensor Photosensor Document sensor PCB
Document tray open sensor Mechanical switch Harness support
CCD HP sensor Photosensor CCD unit
Manual insertion sensor Photosensor Engine PCB
Registration sensor Photosensor Engine PCB
Cassette sensor Photosensor Engine PCB
Paper ejection sensor Photosensor Paper ejection sensor PCB
Toner sensor Photosensor Toner sensor (LED) PCB and toner
sensor (light-receiver) PCB
Cover sensor Photosensor Toner sensor (LED) PCB
Jam sensor Photosensor Heat-fixing unit
Heater thermistor Thermistor Heat-fixing unit
In-casing temperature sensor Thermistor Left-hand plate of the main chassis
• Document front sensor which detects the presence of documents.
• Document rear sensor which detects the leading and trailing edges of pages to tell the control
circuitry when the leading edge of a new page has reached the starting position and when the
scan for that page is over.
• Document tray open sensor which detects whether the document tray is closed.
• CCD HP sensor which detects whether the CCD unit is placed in the home position.
• Manual insertion sensor which detects whether paper is inserted manually through the paper slot
or whether paper fed through the paper cassette has jammed.
• Registration sensor which detects the leading and trailing edges of recording paper, which
allows the controller to determine the registration timing and check paper jam.
• Cassette sensor which detects whether the paper cassette is loaded.
• Paper ejection sensor which detects whether the recording paper goes out of the machine.
• Toner sensor which detects whether there is toner or a toner cartridge is loaded.
• Cover sensor which detects whether the front cover is closed.
• Jam sensor which detects whether paper is jammed inside the heat-fixing unit.
• Heater thermistor which allows the controller to monitor the temperature of the heater roller of
the fixing unit.
• In-casing temperature sensor which allows the controller to monitor the temperature inside the
machine.