OKIDATA OF1050, Service Manual

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Service Guide OF1050/2350/2450
Chapter 3 Board Description/Printer Operation
3.19 Major Trouble Errors
3.19.01 Fuser Error
The fuser error indicates an error in thermister on heater. In case the fuser error occurs at the time of
printing, the heater is turned off immediately, but the printing continues of that page. However, if the error
occurs before the write sensor is turned on, the motors stop.
3.19.02 Fan Error
A fan error is generated when the FANSNS signal lead goes "1" while the fan is running at full speed.
Operation of the FANSNS signal when the fan is turned on is described below.
Since the fan alarm is not monitored during printing, the fan alarm does not appear until the completion of
printing operation. In other words, the printing will continue even if the fan alarm occurs during printing.
3.19.03 Toner Low Detection
Composition The device consists of a stirring gear which rotates at a constant rate, a stirring bar and a
magnet on the stirring bar. The stirring bar rotates through the link on a protrusion in the stirring gear.
The configuration of stirring bar in the figure below may differ. The principle of toner detection, however,
remains the same.
Operation Toner Low is detected by monitoring the time interval between the encounter of the magnet set
on the sensor lever and the magnet on the stirring bar.
• Operation during toner full state
When the stirring bar magnet rotates past the toner sensor magnet, the sensor lever toggles the toner
optical sensor on the power supply board.
When the magnet on the stirring bar reaches the maximum height, since the other side is being dipped in
the toner, the stirring bar rotates at a constant speed.