Lexmark C912 Service Manual - Page 193

5055-xxx Belt up/down In monochrome printing, switching to color printing is not required. To avoid unnecessary wear of the photosensitive drum by the cleaning blade, this operation is stopped with the electromagnetic clutch in drive 1. The transfer belt is lowered so as not to touch the photosensitive drum during color printing. The transfer belt moves up and down with the switching shaft cam by the electromagnetic clutch in drive 1. The belt position is used to detect the cam position with the photo sensor, using the fan shaped light blocking plate attached to the switching shaft. Printing with the transfer belt lowered is called monochrome mode and color printing is called color mode. Expansion paper feeder The optional expansion paper feeder can be installed at the lower part of the main unit. Including the main unit, up to five layers of cassettes can be used for cassette paper feeding. Diagnostic aids 3-43