Lexmark Optra C710 Service Manual page 47

5016-001
Detecting toner level
The toner level sensor is installed in the bottom of the printer and
emits light from infrared LED's mounted in the sensor assembly, to
mirrors mounted at an angle of the cartridge sensor window.
•
No toner in cartridge: Will be high "H"
•
Toner left in cartridge: Will be low "L" (toner sensor output at
connector)
General Information
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