Ricoh M156, Service Manual

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Image Quality
M156/M157/M176/M177 6-12 SM
6.4 IMAGE QUALITY
6.4.1 OVERVIEW
Image problems may appear at regular intervals that depend on the circumference of certain
components. The following diagram shows the possible symptoms (black or white dots at regular
intervals).

Abnormal image at 29.8 mm intervals: Charge roller

Abnormal image at 37.7 mm intervals: Registration roller

Colored spots at 37.9 mm intervals: Print cartridge (Development roller)

Abnormal image at 45.8 mm intervals: Transfer roller

Colored spots at 75.3 mm intervals: Print cartridge (OPC drum)

Abnormal image at 94.2 mm intervals: Fusing unit (Pressure roller)

Abnormal image at 93.1 mm intervals: Fusing unit (Hot roller)

Abnormal image at 100.5 mm intervals: Paper feed roller