What Is Wire Harness?; Electric Wire - Toyota Automobile Electrical Repair And Modification

A–2
Terminal (Female)
Housing (Female)
A
Wire
Harness
(W/H)
B = Black
L = Blue
V = Violet
R = Red
P = Pink
Y = Yellow
O = Orange
6
INTRODUCTION–GENERAL INFORMATION
Housing (Male)
Terminal (Male)

Electric Wire

Terminal
Housing
Fuse
J/B
(Junction Block)
R/B
(Relay Block)
Other
Insulator
Copper Wires
(Conductor)
W = White
BR = Brown
SB = Sky Blue
G = Green
LG = Light Green
GR = Gray
Wire Harness Repair Manual (RM1022E)

What is Wire Harness?

The wire harness (W/H) is systems of electric wires for
automobiles to connect all the electronics parts in
automobile electrically and work them. As more electronics
parts are introduced in automobiles recently, the electric
wires used for the wire harness are increasing in number
and the structure is becoming more complicated. As a
result of that, there are hundreds of connectors, which is
the parts which connects wires mechanically and
electrically, in one vehicle. Therefore, numbers of the
connector terminal (Terminal) or the connector housing
(Housing) are designed to meet many kinds of uses of
circuits. Various components have been improved to
ensure the product reliability or realize a wider space in the
vehicles.
Wire Harness Components
Wire harness mainly consists of wires, terminals, or
housings.
There are various components are designed for many
parts of vehicles, such as one with high heat–resistance,
water–resistance, or bending ability, ones have different
current capacities, or ones are hardly influenced by
electromagnetic noise.
Electric Wire
The electric wires used for the wire harness consists of the
conductor made from numbers of twisted mild copper wire
with a diameter of less than 0.5 mm and the insulator
surrounding the conductor.
The insulator is generally made from vinyl chloride and
covers the conductor with even thickness. The insulators
are color–coded in order to distinguish each wire. The base
colors or the stripe patterns is used to make difference
between insulators. Each color of wires is indicated by the
abbreviation in the repair manual and the electrical wiring
diagram.