Brother MFC5840CN Service Manual page 2

Preface
This Service Manual is intended for use by service personnel and details the specifications,
construction, theory of operation, and maintenance for the Brother machines noted on the front cover.
It includes information required for troubleshooting and service--disassembly, reassembly, and
lubrication--so that service personnel will be able to understand equipment function, repair the
equipment in a timely manner and order spare parts as necessary.
To perform appropriate maintenance so that the machine is always in the best possible condition for
the customer, service personnel must adequately understand and apply this manual.
How this manual is organized
This manual is made up of nine chapters and appendices.
CHAPTER 1 PARTS NAMES AND FUNCTIONS
Contains external views and names of components and describes their functions. Information about
the keys on the control panel is included to help you check operation or make adjustments.
CHAPTER 2 SPECIFICATIONS
Lists the specifications of each model, which enables you to make a comparison of different models.
CHAPTER 3 THEORY OF OPERATION
Gives an overview of the scanning and printing mechanisms as well as the sensors, actuators, and
control electronics. It aids in understanding the basic principles of operation as well as locating
defects for troubleshooting.
CHAPTER 4 TRANSFER OF DATA LEFT IN THE MACHINE TO BE SENT FOR REPAIR
Describes how to transfer data left in the machine to be sent for repair. The service personnel should
instruct end users to follow the transfer procedure given in this chapter if the machine at the user site
cannot print received data due to the printing mechanism defective. End users can transfer received
data to another machine to prevent data loss.
CHAPTER 5 DISASSEMBLY/REASSEMBLY AND LUBRICATION
Details procedures for disassembling and reassembling the machine together with related notes. The
disassembly order flow provided enables you to see at a glance the quickest way to get to
component(s) involved.
At the start of a disassembly job, you check a disassembly order flow that guides you through a
shortcut to the object components.
This chapter also covers screw tightening torques and lubrication points to which the specified
lubricants should be applied during reassembly jobs.
CHAPTER 6 ADJUSTMENTS AND UPDATING OF SETTINGS REQUIRED AFTER PARTS
REPLACEMENT
Details adjustments and updating of settings, which are required if the head/carriage unit, main PCB
and some other parts have been replaced.
CHAPTER 7 CLEANING
Provides cleaning procedures not covered by the User's Manual. Before starting any repair work,
clean the machine as it may solve the problem concerned.
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