8DÐ4 WIRING SYSTEM
The chassis electrical system is a 12Ðvolt system with a
negative ground polarity.
Wire size are appropriate to respective circuits, and
classified by color. (The classification of harnesses by
color is shown on the circuit diagram for ease of harness
identification.)
The wire size is determined by load capacity and the
length of wire required.
The vehicle harnesses are: body harness, chassis
harness, engine room harness, instrument harness,
transmission harness, engine ECGI harness, dome light
harness, door harness, rear body harness, tailgate
harness, SRS harness and battery cables.
The harnesses are protected either by tape or corrugated
tube, depending on harness location.
The circuit for each system consists of the power source,
wire, fuse, relay, switch, load parts and ground, all of
which are shown on the circuit diagram.
In this section, each electrical device is classified by
system.
For major parts shown on the circuit based on the circuit
diagram for each system, a summary, diagnosis of
troubles and inspection procedures are detailed.
Notes for Working on Electrical
Items
Disconnecting the Battery Cable
1. All switches should be in the ÒOFFÓ position.
2. Disconnect the battery ground cable (2).
3. Disconnect the battery positive cable (1).
CAUTION: It is important that the battery ground
cable be disconnected first. Disconnecting the
battery positive cable first can result in a short circuit.
Connecting the Battery Cable
Follow the disconnecting procedure in the reverse order.CAUTION: Clean the battery terminal and apply a
light coat of grease to prevent terminal corrosion.
Disconnecting the Connector
Some connectors have a tang lock to hold the connectors
together during vehicle operation.
Some tang locks are released by pulling them towards
you (1).
Other tang locks are released by pressing them forward
(2).
Determine which type of tang lock is on the connector
being handled.
Firmly grasp both sides (male and female) of the
connector (3).
Release the tang lock and carefully pull the two halves of
the connector apart.
Never pull on the wires to separate the connectors (4).
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General Description
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WIRING SYSTEM 8DÐ13
Wiring Ð Wire Size
The size of wire used in a circuit is determined by the
amount of current (amperage), the length of the circuit,
and the voltage drop allowed. The following wire size and
load capacity, shown below, are specified by AWG
(American Wire Gauge). (Nominal size means
approximate cross sectional area (1).)
Wiring Ð Wire Size Table
Nominal sizeCross sectional Outside diameter Allowable
area (mm2) (mm) current (A)
0.3 0.372 1.5 9
0.5 0.563 1.7 12
0.85 0.885 1.9 16
1.25 1.287 2.2 21
2 2.091 2.7 28
3 3.296 3.6 37.5
5 5.227 4.4 53
8 7.952 5.5 67
15 13.36 7.0 75
20 20.61 8.2 97
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8DÐ16 WIRING SYSTEM
Circuit Breaker
The circuit breaker is a protective device designed to
open the circuit when a current load is in excess of rated
breaker capacity. If there is a short or other type of
overload condition in the circuit, the excessive current will
open the circuit between the circuit breaker terminals.
The reset knob (1) pops out when the circuit is open. Push
the reset knob in place to restore the circuit after repairing
it.
Relay
Battery and load location may require that a switch be
placed some distance from either component. This
means a longer wire and a higher voltage drop (1).
The installation of a relay between the battery and the
load reduces the voltage drop (2).
Because the switch controls the relay, amperage through
the switch can be reduced.
Push
LOAD
12LOAD
RELAY
D08RW404
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