Service manual

CA-iii
Preface
This manual has been designed as a supplement to the CM-151 CA/CB training manual (923-3351TRM).
It provides circuit descriptions as well as troubleshooting flowcharts for both CA and CB chassis. Each
description includes schematic diagrams of the particular section(s) being discussed. These inclusions
represent a change from some recent training manuals. Moreover, this manual is divided into two distinct
sections, respectively, for CA and CB chassis. Such an arrangement should prevent confusion between the
two.
Many servicers prefer to use their training manuals in conjunction with the corresponding service manuals.
As such, the schematics contained in this training supplement were drawn to be fairly generic. However, as
a concession to those who desire a quick reference, tables that include part numbers of major components
have been supplied in each applicable circuit description. Note that these part numbers should only be
applied to those sets which fall under component level repair warranty. (32 and 36 sets have a module
replacement warranty.) Hence, when a table refers to all models, it can only apply with certainty to all
component level repairable modules. Likewise, in the troubleshooting section, flowcharts will often instruct
the repair technician to replace a certain component under a particular situation. Again, such instruction
concerns component level repair sets. Still, the flowcharts provide useful information for diagnosing a
problem on component level warranty modules and replacement warranty modules alike.
Frequently, the tables refer the reader to the service manual for particular models associated with given
parts, particularly with regard to the CA chassis. This is because at the time this manual was produced,
there were 81 variants of the CA chassis in the field. In any case, parts referencing is really beyond the
scope of a training manual. Furthermore, it is a good idea when looking up part numbers to refer to up-to-
date service information. Generally speaking, training in circuit theory and operation does not change when
part numbers do.
Finally, be sure to take special note of the safety information supplied in this manual. General safety infor-
mation is provided for both chassis on the reverse side of the front cover. High voltage protection instruc-
tion for the CA chassis is located on the page following the general safety page and for the CB chassis at the
start of the second section of this manual.