Canon imageRUNNER ADVANCE C5000 Series Technical Workbook page 146

14) Remove 2 connectors [1]. Remove 1 screw [2] and the Drum Speed Detection Unit [3].
15) Remove the contamination at the two locations on the Drum Speed Detection Sensor [1] with the blower
brush.
16) Clean the both surfaces of the disk-shaped encoder [1] with alcohol.
[Caution] Be sure not to bend the encoder when cleaning it.
17) Install the Drum Speed Detection Unit to the Drum Drive Unit with a screw. Then connect the two
connectors.
18) Open the Process Unit Inner Cover.
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