
The automotive electrical system in my opinion is the most important support system of a modern day car or truck. When you master diagnosis and repair of it the skills can be used in countless other areas of the automobile.
Imagine a vehicle without an electrical system. The gasoline engine would not run. Electricity provides the needed spark for combustion plus the power needed for cranking. Near the bottom of this page are some exciting articles that review electrical principles, component operation, circuit design and testing procedures.
Learning this stuff is absolutely necessary to be successful in diagnosing complex automobile systems efficiently. There are excellent resources on this page to help you accomplish this, both free and inexpensive. The rest of this page is an overview of what can be found in this repair module.
The automotive electrical systems video on the left is on amazon instant video. For less then 3 bucks it provides more then an hour of training. Most of the essential basics of automotive electronic diagnostics such as current, voltage, electronic symbols and a lot more are covered very well.
Put yourself on the cutting edge. The recent advances that have been deployed in the auto electronics field have allowed the efficiency of the vehicle to increase greatly while at the same time increasing the overall reliability.
It's new technology that allows for greater fuel economy demanded by both the federal government C.A.F.E. (corporate average fuel economy) ratings and keep the car buying public happy. The amazing part is, these mileage improvements came at the same time as horsepower and torque increases.
Both professional technicians and do-it-yourself auto mechanics need to be able to diagnose both electrical and electronic systems. Some Diy car mechanics become confused about the different meaning of these terms.
Electrical automotive systems refer to the wiring harnesses and connectors, the electrical car parts such as starter motors and alternators, vehicle lighting, relay's and switches just to name a few.
Automotive electronics is a reference to computer control modules and other black box type items used to control engine operation. They can be critical vehicle systems such as fuel injection or driver requirements like instrument clusters. A good understanding of electrical principles is important to properly diagnose any systems that are monitored, controlled, or operated by electricity.
The book on the left has been a classic text for electronics enthusiasts and provides a strong foundation. Hold off buying it until you finish this page. This article leads you to more free articles that will support your understanding of the different automobile electrical systems that you will run into during auto repair and diagnosis.
This can be a tough to learn subject that might not be right for everybody. But With a full understanding of electrical principles and operation, diagnosis will be easier and faster. I will put together articles below that cover the basics first and work their way up to more complex electrical principles.
The first article explains the basic principles of electricity. I then get into using ohms law to determine voltage, current, resistance, and voltage drop. These measurements are often used during diagnosis, or when following car wiring diagrams to solve problems.

I will cover other items related to auto electrical systems including basic types of electrical circuits and their use in the modern day automobile. Another extremely interesting principle I talk about below is electromagnetism. The car relies heavily on the use of magnetism.
Wheel speed sensors, cam sensors, crankshafts sensors, and many other engine performance related components use magnetism principles. So let's get started and dig into some articles.
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This is a good place to start. Understanding the facts about voltage,
Amps, and resistance (Ohms) helps mechanics diagnose and repair complex
electrical systems. Here I explain the definitions of these
automotive electrical terms.
Open your mind to fixing electrical components instead of buying
replacement parts. You can't always fix them but at least look at my
page about
repairing car electronics.
Automotive electrical problems can only be caused by 3 root failures. As complex as these systems can be the solutions are always traced back to these
electrical circuit malfunctions.
Have you ever started diagnosing a car problem and thought to yourself, I
bet it's a bad relay? Stop wondering and start testing with these 3
quick ways of
testing automotive relays.
If you prefer to learn from video this next link is for you. This is a five minute video that shows you the method I use for electrical diagnosis and how to use and find automotive
wiring diagrams.
Yet another popular short video I put together about finding shorts that
blow fuses. These can be hard to find without following a plan. This
video shows you how to stop wasting fuses and quickly find
electrical shorts.
Replacing car parts that are not defective is a big problem for auto mechanics. If you do your own electrical repairs you can solve this problem with one inexpensive tool. Learn about testing with a
multimeter.
When do it yourself car mechanics tackle electrical problems on their own vehicle it often starts with a blown fuse. This next article covers circuit breakers, fuses and other
automotive circuit protection.
Learn about automobile wiring. See what kinds you will run into
when diagnosing open or shorted wiring harnesses. This next article is
all about the sizes, shapes and types of
automotive wiring.
Understanding how current flow and resistors work together
in power distribution helps you think like a mechanic when your staring
at wiring diagrams. This next article discusses 4 types of
automotive resistors.
I know that magnetism can be a dry subject. But your car will not start
or run without it. Learn about magnetic crank sensors and
automotive electrical magnetism.
Here is a link to an article on my online auto repair blog (opens new
window) about electrical theories and the math formula that can be used
in diagnosis. This article talks about how to use ohms law to fix common car problems.
Often replaced car electrical parts. Starting and charging is what gets
you out of the driveway and back again! Learn how your car battery works
together with
starters and alternators.
The homepage is a great place to go to find out what else is covered on
this auto repair website. This next link takes you from automotive
electrical to DIY car repair advice.