Brother MFC8500 Service Manual page 159

Trouble
(12) Faulty image registration
(Leading edge of image
starts too late on paper)
(13) Image distortion or
improper image alignment
(14) Blurred at either side
At the printer side
Instruct the user not to load paper exceeding the limit on the
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paper cassette(s).
Instruct the user to use the recommended types of paper.
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Replace the paper cassette(s).
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Check the position of the registration sensor.
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Replace the drive gear ASSY.
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In communications
Check the following components:
- Error code displayed. (Refer to Section 1, "ERROR
INDICATION" in this chapter.)
- NCU PCB
- Main PCB
At the scanner
Check the following components:
- Document take-in roller, separation roller, and their
related sections
- Document feed roller and its related gears
- Scanner motor and its harness
- Main PCB
At the printer side
Check that the laser unit is secured with the screws without
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looseness.
Check the connection of the polygon motor harness on the
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engine PCB.
Check the connection of the laser flat cable on the main PCB.
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Replace the laser unit.
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At the printer side
Check that the equipment is placed on a flat surface.
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Shake the toner cartridge horizontally. If the problem
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persists, replace it.
Clean the laser beam window (glass) on the laser unit.
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Replace the laser unit.
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VI - 25
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Action to be taken
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