Canon DADF-J1, Service Manual

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COPYRIGHT© 2001 CANON INC. CANON DADF-J1 REV.0 MAR. 2001
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INTRODUCTION
The following rules apply throughout this document:
As a rule, the descriptions in this documentation are based on the following:
1. As needed, the work of each function and its relationship with electrical and me-
chanical parts are explained; where applicable, the timing at which associated parts
are driven are also outlined.
In a diagram, the symbol
indicates a path of mechanical drive; the symbol
accompanied by a notation indicates the flow of an electrical signal.
The expression “power-on” means turning on the power switch, closing the front
door, and closing the delivery door so that the parts of the machine are supplied with
power.
2. In a digital circuit, the state of a signal is indicated by ‘1’ if its voltage level is high
and by ‘0’ if low. The level of voltage, however, differs from circuit to circuit.
The machine uses a CPU; however, since the internal functions of a CPU is outside
the scope of a service person, detailed explanations are omitted from descriptions. In
this document, a circuit diagram may cover from sensors to inputs of a controller
PCB or from outputs of a controller PCB to loads, or it may be a functional diagram.
The descriptions of the machine are subject to change for product improvement, and ma-
jor changes will be communicated in the form of Service Information bulletins.
All service persons are expected to be fully familiar with the contents of this Service
Manual and Service Information bulletins to develop a good understanding of the machine,
equipping themselves with the ability and skill to identify faults and to maintain the machine
in good order.