Canon imageRUNNER ADVANCE C5000 Series Technical Workbook page 138

14) Removet the two connectors [2] and 3 screws [3] to remove the Drum Drive Unit (Bk) [1].
15) Remove 2 connectors [1]. Remove 1 screw [2] and the Drum Speed Detection Unit [3].
16) Remove the contamination at the two locations on the Drum Speed Detection Sensor [1] with the blower
brush.
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