Komatsu PC500LC-10R, Shop Manual

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PRECAUTIONS FOR HANDLING ELECTRICAL EQUIPMENT
To maintain the performance of the machine over a long period, and to prevent failures or troubles before they
occur, correct "operation", "maintenance and inspection" "troubleshooting", and "repairs" must be performed.
This section deals particularly with correct repair procedures for mechatronics components and is aimed at im-
proving the quality of repairs. For this purpose, it describes the working procedures in "Handling of electrical
equipment".
Handling wiring harnesses and connectors
• Wiring harnesses consist of wires connecting one compo-
nent to another component, connectors used for connect-
ing and disconnecting one wire from another wire, and pro-
tectors or tubes used for protecting the wires.
• Compared with other electrical components fitted in boxes
or cases, wiring harnesses are likely to be directly affected
by rain water, heat, or vibration. Furthermore, during in-
spection and repair operations, they are frequently re-
moved and installed again, so they are likely to suffer de-
formation or damage. For this reason, it is necessary to be
extremely careful when handling and maintenance of the
wiring harnesses.
Main causes of failure in wiring harness
Defective contact of connectors (defective contact between male and female connectors)
Problems with defective contact are likely to occur because the
male connector is not properly inserted into the female connec-
tor,or because one or both of connectors are deformed or the
position is not correctly aligned, or because there is corrosion
or oxidization of the contact surfaces. The corroded or oxidized
contact surfaces may become shiny again (and contact may
become normal) by connecting and disconnecting the connec-
tors approximately 10 times.
Defective crimping or soldering of connectors
The pins of the male and female connectors are attached to
wires by crimping or soldering. If excessive force is applied to
the wire, the jointed portion (1) may become loose, and it may
result in a defective connection or breakage.
00 INDEX AND FOREWORD PRECAUTIONS FOR HANDLING ELECTRICAL EQUIPMENT
PC500LC-10R 00-35