Glossary Of Terms And Symbols

BATTERY

Stores chemical energy and converts it into electrical energy. Provides DC current for the auto's various electrical circuits.

GROUND

The point at which wiring attaches to the Body, thereby providing a return path for an electrical circuit; without a ground, current cannot flow.

CAPACITOR (Condenser)

A small holding unit for temporary storage of electrical voltage.

CIGARETTE LIGHTER

An electric resistance heating element.

2. DOUBLE FILAMENT

HEADLIGHTS 1 SINGLE Current flow causes a headlight ' FILAMENT filament to heat up and emit light. A headlight may have either a single (1) filament or a double (2) filament

2. DOUBLE FILAMENT

CIRCUIT BREAKER

Basically a reusable fuse, a circuit breaker will heat and open if too much current flows through it. Some units automatically reset when cool, others must be manually reset.

HORN

An electric device which sounds a loud audible signal.

DIODE

A semiconductor which allows current flow in only one direction.

IGNITION COIL

Converts low-voltage DC current into high-voltage ignition current for firing the spark plugs.

DIODE, ZENER

A diode which allows current flow in one direction but blocks reverse flow only up to a specific voltage. Above that potential, it passes the excess voltage. This acts as a simple voltage regulator.

PHOTODIODE

The photodiode is a semiconductor which controls the current flow according to the amount of light.

DISTRIBUTOR, IIA

Channels high-voltage current from the ignition coil to the individual spark plugs.

FUSE

A thin metal strip which burns through when too much current flows through it, thereby stopping current flow and protecting a circuit from damage.

FUSIBLE LINK

(for Medium Current Fuse) A heavy-gauge wire placed in high amperage circuits which burns through on overloads, thereby protecting the circuit.

The numbers indicate the crosssection

(for High Current Fuse or

Fusible Link)

LIGHT

Current flow through a filament causes the filament to heat up and emit light.

LED (LIGHT EMITTING DIODE)

Upon current flow, these diodes emit light without producing the heat of a comparable light.

METER, ANALOG

Current flow activates a magnetic coil which causes a needle to move, thereby providing a relative display against a background calibration.

METER, DIGITAL

Current flow activates one or many LED's, LCD's, or fluorescent displays, which provide a relative or digital display.

MOTOR

A power unit which converts electrical energy into mechanical energy, especially rotary motion.

FUEL

RELAY

Basically, an electrically operated

1. NORMALLY switch which may be normally CLOSED closed (1) or open (2).

Current flow through a small coil creates a magnetic field which either opens or closes an attached switch.

2. NORMALLY OPEN

RELAY, DOUBLE THROW

A relay which passes current through one set of contacts or the other.

SPEAKER

An electromechanical device which creates sound waves from current flow.

SWITCH, MANUAL

1. NORMALLY OPEN

2. NORMALLY CLOSED

Opens and closes circuits, thereby stopping (1) or allowing (2) current flow.

RESISTOR

An electrical component with a fixed resistance, placed in a circuit to reduce voltage to a specific value.

SWITCH, DOUBLE THROW

A switch which continuously passes current through one set of contacts or the other.

RESISTOR, TAPPED

A resistor which supplies two or more different non adjustable resistance values.

RESISTOR, VARIABLE or RHEOSTAT

A controllable resistor with a variable rate of resistance. Also called a potentiometer or rheostat.

SWITCH, IGNITION

A key operated switch with several positions which allows various circuits, particularly the primary ignition circuit, to become operational.

SWITCH, WIPER PARK

Automatically returns wipers to the stop position when the wiper switch is turned off.

(Reed Switch Type)

SENSOR, SPEED

Uses magnetic impulses to open and close a switch to create a signal for activation of other components.

TRANSISTOR

A solidstate device typically used as an electronic relay; stops or passes current depending on the voltage applied at "base".

TRANSISTOR

A solidstate device typically used as an electronic relay; stops or passes current depending on the voltage applied at "base".

SHORT PIN

Used to provide an unbroken connection within a junction block.

WIRES

CONNECTED

SOLENOID

An electromagnetic coil which forms a magnetic field when current flows, to move a plunger, etc.

(2) SPLICED

Wires are always drawn as straight lines on wiring diagrams.

Crossed wires (1) without a black dot at the junction are not joined;

crossed wires (2) with a black dot or octagonal ( ) mark at the junction areO spliced (joined) connections.

[Engine Compartment]

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