Ricoh C211 Service Manual page 648

8. Drum Rotation Trouble
< Phenomenon>
8-1. The drum does not rotate. When the drum rotation button is pressed, the drum begins to
rotate, but immediately afterwards, the buzzer rings and the drum stops rotating.
< Possible causes>
1.
2.
Contamination on the light emitting
and light detecting surfaces of the first
drum position sensor [A] maintains the
sensor ON condition (interrupted);
therefore, the drum is always judged to
be at the sensor on position.
[A]
The first drum position sensor is faulty.
< Countermeasure>
1.
2.
Clean the light emitting and light
detecting surfaces [B] of the first drum
position sensor [A].
* Remove the sensor and clean up
ink, oil, and the paper powder on it.
[B]
Replace the first drum position sensor
[A].
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