Ricoh FT4460, Service Manual, Page: 366 / 413

28 February 1989
1.21 OPTICS UNIT CONTROL FAILURE - 2 (Copy Cycle)
- Phenomenon -
The scanner moves all the way to the right (return position) and strikes the
copier frame.
- Possible Causes -
1. Scanner motor malfunction
2. I/O control board malfunction
3. Electrical noise caused by a high voltage leak from the charge corona
may result in a program error that causes the scanner control failure.
- Actions -
1.
2.
3 .
Check the encoder output of the scanner drive motor on the I/O control
board (CN301-B14 and CN301-B15) while slowly turning the scanner
motor pulley. Each phase of the encoder should show a change of state
(5V –> 0V –> 5V).
If each phase shows a change of state in the above check, replace the
I/O control board. If there is no change of state (either phase), replace
the scanner drive motor.
Find out what caused the high voltage leak and correct the problem.
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