ABBREVIATIONS

BATTERY

HEADLIGHTS Current flow causes a headlight

Stores chemical energy and

1. SINGLE

filament to heat up and emit light.

converts it into electrical energy.

A headlight may have either a

Provides DC current for the auto's

FILAMENT

single (1) filament or a double (2)

various electrical circuits.

filament.

CAPACITOR (Condenser)

2. DOUBLE

A small holding unit for temporary

FILAMENT

storage of electrical voltage.

CIGARETTE LIGHTER

HORN

An electric resistance heating

An electric device which sounds a

element.

loud audible signal.

CIRCUIT BREAKER

Basically a reusable fuse, a circuit

breaker will heat and open if too

IGNITION COIL

much current flows through it. Some

Converts low±voltage DC current

units automatically reset when cool,

others must be manually reset.

into high±voltage ignition current

DIODE

for firing the spark plugs.

A semiconductor which allows

current flow in only one direction.

DIODE, ZENER

LIGHT

A diode which allows current flow

Current flow through a filament

in one direction but blocks reverse

causes the filament to heat up

flow only up to a specific voltage.

and emit light.

Above that potential, it passes the

excess voltage. This acts as a

simple voltage regulator.

DISTRIBUTOR, IIA

LED (LIGHT EMITTING DIODE)

Channels high±voltage current

Upon current flow, these diodes

from the ignition coil to the

emit light without producing the

individual spark plugs.

heat of a comparable light.

FUSE

METER, ANALOG

A thin metal strip which burns

Current flow activates a magnetic

through when too much current

coil which causes a needle to

flows through it, thereby stopping

move, thereby providing a relative

current flow and protecting a

display against a background

circuit from damage.

calibration.

FUSIBLE LINK

METER, DIGITAL

(for Medium Current Fuse)

A heavy±gauge wire placed in

Current flow activates one or

high amperage circuits which

many LED's, LCD's, or fluorescent

burns through on overloads,

FUEL

displays, which provide a relative

thereby protecting the circuit.

(for High Current Fuse or

or digital display.

The numbers indicate the cross±

Fusible Link.)

section surface area of the wires.

GROUND

MOTOR

The point at which wiring attaches

A power unit which converts

to the Body, thereby providing a

M

electrical energy into mechanical

return path for an electrical circuit;

energy, especially rotary motion.

without a ground, current cannot

16

flow.

RELAY

Basically, an electrically

SPEAKER

operated switch which may

An electromechanical device

1. NORMALLY

be normally closed (1) or

which creates sound waves from

CLOSED

open (2).

current flow.

Current flow through a

small coil creates a

2. NORMALLY

magnetic field which either

SWITCH, MANUAL

opens or closes an

OPEN

attached switch.

Opens and

1. NORMALLY

closes circuits,

OPEN

thereby

RELAY, DOUBLE THROW

stopping (1) or

A relay which passes current

2. NORMALLY

allowing (2)

current flow.

through one set of contacts or the

CLOSED

other.

RESISTOR

SWITCH, DOUBLE THROW

An electrical component with a

A switch which continuously

fixed resistance, placed in a circuit

passes current through one set

to reduce voltage to a specific

of contacts or the other.

value.

RESISTOR, TAPPED

SWITCH,

A resistor which supplies two or

IGNITION

more different non adjustable

A key operated switch with

resistance values.

several positions which allows

various circuits, particularly the

RESISTOR, VARIABLE or

primary ignition circuit, to

RHEOSTAT

become operational.

SENSOR (Thermistor)

SWITCH, WIPER PARK

A resistor which varies its

Automatically returns wipers to

resistance with temperature.

the stop position when the wiper

switch is turned off.

SENSOR, ANALOG SPEED

TRANSISTOR

Uses magnetic impulses to open

A solidstate device typically used

and close a switch to create a

as an electronic relay; stops or

signal for activation of other

passes current depending on the

components.

voltage applied at ªbase.º

SHORT PIN

WIRES

Used to provide an unbroken

(1)

NOT

Wires are always

connection within a junction block.

CONNECTED

drawn as straight lines

on wiring diagrams.

Crossed wires (1)

without a black dot at

the junction are not

SOLENOID

joined; crossed wires

An electromagnetic coil which

(2) with a black dot or

octagonal ( ) mark at

forms a magnetic field when

(2)

SPLICED

the junction are spliced

current flows, to move a plunger,

etc.

(joined) connections.

: J/B No. 3

Behind Combination Meter (See Page 18)