Chapter 2 Troubleshooting; Introduction; Precautions - Brother DCP-J4110DW Service Manual

CHAPTER 2 TROUBLESHOOTING

1

INTRODUCTION

This section gives the service personnel some of the troubleshooting procedures to be followed
if an error or malfunction occurs with the machine. It is impossible to anticipate all of the
possible problems which may occur in future and determine the troubleshooting procedures, so
this section covers some sample problems. However, those samples will help service personnel
pinpoint and repair other defective elements if he/she analyzes and examines them well.
1.1

Precautions

Be sure to observe the following to prevent any secondary troubles from happening during
troubleshooting.
(1) AC power codes must be removed from their outlets before starting any removal of covers
and PCBs, adjustments and conductivity test using a tester.
(2) When disconnecting the connectors, hold the connector housings. Do not pull the lead
wires.
(3) Static electricity charged in your body may damage electronic parts.
Before handling the PCBs, touch a metal portion of the machine to discharge static
electricity charged in your body. When transporting PCBs, be sure to wrap them in
conductive sheets.
When replacing the PCBs, put on a grounding wrist band and perform the job on a
conductive mat.
Also take care not to touch the conductor sections on the flat cables.
(4) Be sure to observe the warnings.
WARNING WARNING
DO NOT use flammable substances such as alcohol, benzine, thinner or any type of spray to
clean the inside or outside of the machine. Doing this may cause a fire or electrical shock.
(5) After repairing the defective section, be sure to check again if the repaired section works
correctly.
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