Ricoh FT4460, Service Manual, Page: 372 / 413

28 February 1989
2 . 5 C O D E # 2 3
- Phenomenon -
SC #23: The sytstem control board does not receive the lead edged signal
(LE) until the scanner reaches the maximum return position.
- Possible Causes -
1. I/O control board malfunction
2. System control board malfunction
3. Scanner motor malfunction
- Action -
Check CN301-B8 on the I/O control board during a copy cycle.
5V: Replace scanner drive motor or I/O control board.
Voltage changes to 0V: Replace system control board. (See the note
below.)
NOTE: Normally, the lead edge signal drops from 5V to 0V just before the
registration clutch turns on, then rises to 5V when the scanner
reaches the “return” position.
2 . 6 C O D E # 2 4
- Phenomenon -
SC #24: The I/O control board does not receive the 1st scanner home
position signal within 20 seconds after the scanner starts.
- Possible Causes -
1.
2.
3 .
4.
5.
I/O control board malfunction
System control board malfunction
Optical scanner overload (binding)
The power supply unit is not sup24V.
The scanner wire is slipping.
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