Electrical Shematic Diagrams

8/3/2019 Electrical Shematic Diagrams

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Wiring Diagrams Wiring

Diagrams Wiring Diagrams

Wiring Diagrams WiringDiagrams Wiring Diagrams

Wiring Diagrams WiringDiagrams Wiring Diagrams

Wiring Diagrams Wiring

Diagrams Wiring Diagrams

Wiring Diagrams


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Schematics

Wiring Diagrams or Schematics use asymbolic language

Understand the symbols and the diagramswill talk to you

What it can tell you is how and where totest the system


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Listen to the Diagram!

Wiring Diagrams explain how a circuit works

All electrical circuits need Power (positivevoltage), conductors, controls, loads.

To understand how a circuit works you musttrace powerflow through the conductors,controls, and loads.


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Power at the top!

Positive voltage is often called power.

Positive voltage usually originates in the topand left side of the diagram.

Ground is usually found at the bottom andright side of the diagram.


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Power(Positive Voltage)

Ground

(Negative Voltage)


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Understand the Symbols

Wiring diagrams contain lots of information

Pay attention to the little details!


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Wires cross withNO electrical contact

Wires cross with soldered splice,will have electrical contact


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What does this

dashed line mean?


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A dashed (or dotted) line can indicate there are other

devices not shown in this picture

To keep the diagram simple, the other electrical

components are not shown

The schematic says a 40 amp fuse is in the fuse/relay box.

The fuse should always have power to it. The dotted line

means there are other items in this fuse/relay box.


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The Engine Compartment

Fuse/Relay Box has other

wires, fuses etc.

The entire Blower Motor Switch is

shown in this schematic

If I wanted to test the blower

fuse I would not be surprised

to find other fuses in this box

To find this switch I would look

for a switch with four wires.


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How many wires goto this relay?

How many wires to thestoplight module?


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More Dashed Lines

A dashed or dotted line can mean there is morethan is shown on the page..

..Or there are other wires hooked to thecircuit, but not shown in the diagram

..Or what controls a switch.


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A dashed or dotted line can mean there

is more than is shown on the page


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Dashed box means the entire

Turn/Hazard Switch is not shown

Terminal Pins A11-A17 are

shown but not pins A1-A10


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A dashed line can indicate there are other

wires common to the circuit, but not shown in

the diagram


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This splice has five

wires in common

(parallel circuits)

This splice has other

wires, in parallel, that arenot shown in this diagram


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The dotted line means

there are other circuitssharing this ground


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A dashed line indicates

switches are linked


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Parking lamp and

Headlamp switches

are gangedtogether as indicated

by the dashed line


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Parking lamp and

Headlamp switches


by the dashed line


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Parking lamp and

Headlamp switches


by the dashed line


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Other switches

inside the headlamp

switch operate

independently

Parking lamp and

Headlamp switches


by the dashed line


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Other switches

inside the headlamp

switch operate

independently

Parking lamp and

Headlamp switches


by the dashed line


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When this coil turns ON

this switch will move

This switch is moved by Temperature

This switch is moved by Pressure


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What does thisdotted line mean?


What does this

dotted line mean?


What does this

dotted line mean?




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Details on Switches


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Draw a continuity block


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Wire Details

Schematics will often indicate

.wire color

.wire gauge size

.circuit code


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Wire Color

Wire Gauge

Circuit Code


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Wire Gauge

4

12

1416

18

20???????

4!

19.0

3.0

2.01.0

0.8

0.5??????

19.0!

Which is the larger wire?AWG

American

Wire Gauge

Metric

wire size


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Not all schematics are the same

Some diagrams will leave out detail

Color Codes change .

.B could be Blue

.OR.

.B could be Black

The order of wire coding can also change


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Circuit Code


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Not all schematics are the same

When you see a new symbol

look it up!

The better you are at reading diagrams...

...the more mental power you will have

il bl t di d fi th bl !!

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Electrical Shematic Diagrams