Car’s electrical system problems

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AUTOMOTIVE MECHANICS

Small engine vehicles

Car’s electrical system problems

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Objective:

✓ Recognize common signs when car’s electrical system is failing.

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Car’s electrical system problems

Modern cars are highly-reliant on electrical systems to function properly. The
alternator, battery, and other electrical and electronic systems control much of
the functionality of the car and if they begin to fail, drivers may experience a
wide variety of issues.

We will see the most common car electrical problems.

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Dead car battery

Car batteries have a “life-span” of
their own. They usually last for about
five

to

seven

years

if

all

the

conditions are right. It also depends
on the build quality of the car battery.

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Corroded, dirty or loose battery terminals

Overtime, a layer of green-like, dusty substance starts to appear on the
terminals. This is because of chemical reactions as most of battery
terminals and the battery poles are made of lead. This can also happen if
the alternator voltage output was too high in some period of time.

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Blown fuses

Fuses are a necessary part of the
electric

installation.

They

are

deliberately weakened spots on the
installation

that

burn

out

once

a

short-circuit or other kind of overload
happens.

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Bad or faulty electrical connections and contacts

Electric installations are highly dependent on a good “flow” of electricity.
Every such spot is a possible weakness in the installation which is, over
time, prone to failure.

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Ground (minus) connection

As mentioned, electric current on the car depends on proper “flow”. It goes
from plus to minus and circulates inside a closed system. Without a good
ground connection, the flow is interrupted.

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Broken or damaged wiring

Car electric problems regarding broken or damaged wiring are one of the
easiest to repair but most complicated to find.

If one is broken or damaged it can be like searching for a needle in a haystack.

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Car bulbs

As with every bulb, they have a life-span of their own and are meant to be
changed after some time.

On most cars the replacement procedure is simple and quick to do. The most
important part is to buy the same light bulb, especially in terms of correct
voltage.

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Sensors

Sensors are the “eyes and ears” of the
whole system and give the basic input
to the ECU.

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Short circuits

Shorts circuits can come from various
reasons like damaged insulation on
wires,

faulty

connectors,

damaged

appliances, or else.

In most cases, short-circuits are very
hard to locate (like with the broken or
damaged wire problem).

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Failed spark plugs or glow plugs

Spark plugs are for petrol engines, glow plugs are for diesel engines.

Spark plugs ignite the mixture inside the cylinder while glow plugs heat up the
cylinder so the fuel can ignite more easily under pressure.

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Car electrical problems with the starter

Car starter is the part of the car that’s in charge of cranking.

If you get car electrical problems of this sort, you won’t be able to start the car
which means you have to solve these problems the moment you notice them.

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Car electrical problems with the alternator

Alternator is a generator that is in charge of providing electric power to your car.
At the same time it recharges the car battery while driving.

Car electric problems regarding the alternator mean that you can run out of
electric power which means you won’t be able to drive.

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Key fob battery

A lot of people get themselves into trouble especially if they don’t have a spare
key at hand. People can easily end up locked out of their own car or not being
able to start it.

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Car horn

A car horn problem is both dangerous and annoying. Dangerous in terms of not
being able to send a warning signal on time, annoying as without a car horn, it’s
like you turned “mute” on the TV.

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ECU (Engine Control Unit)

This is the brain of the whole network
and

is

essentially

the

computer

running your car.

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Now you can recognize common signs when

car’s electrical system is failing.