INTRODUCTION
The descriptions in this Service Manual are based on he following rules:
1.In each chapter, the uses of the function in question and its relationship to electrical and mechanical systems are discussed and the timing of operation of its associated parts is explained by means of outlines and diagrams.
In the diagrams, the symbol 
represents a mechanical path, while the symbol 
with a name next to it indicates the flow of an electric signal.
The expression “turn on the power” means turning on the power switch, closing the front cover, and closing the delivery cover so that the machine will be supplied with power.
2.In circuit diagrams (digital), a signal whose level is High is expressed as being ‘1’, while a single whose level is Low is expressed as being ‘0’; the level of voltage, how- ever, varies from circuit to circuit.
The machine uses CPUs, whose internal mechanisms cannot be checked in the field, and, therefore, are not explained. In addition, the machine’s PCBs are not intended for repairs at the user’s and, therefore, are explained by means of block diagrams: two types are used, i.e., between sensors and inputs of PCBs equipped with a control or drive function and between outputs equipped with a control or drive function and loads; in ad- dition, functional block diagrams are used at times.
Changes made to the machine for product improvement are communicated in the form of a Service Information bulletin as needed. All service persons are expected to go through all service documentation including the bulletins and be equipped to respond to the needs of the field (as by being able to identify possible causes of problems).
COPYRIGHT © 2001 CANON INC. | CANON CLC5000 REV.0 JAN. 2001 | iii |