This multi-part blog series breaks down a vehicle’s electrical system into easy-to-understand chunks. Part 1 was an overview of the basic principles of auto electrical systems. In Part 2, we will discuss the 3 main auto electrical systems and circuits, including the ignition & starter, auto lights, and auxiliary systems. We will cover how these components work, troubleshoot common issues, and discuss repairs & maintenance.

How Auto Electrical Systems Work

It may seem like magic, but all your car’s cool features actually work through a complicated wiring network. A vehicle wiring harness is the main body of an auto electrical system. It is a group of wires designed to safely and efficiently deliver electricity from the car battery to devices throughout the entire automobile. 

How Auto Electrical Circuits Work

Every electric-powered component in your vehicle works because of an electrical circuit. Electrical circuits are circular routes that electrical currents (aka electrons) flow through. The electrical current / electrons originates from the power source (+ battery terminal) and moves through the fuse. Next, the current flows to the switch and into the load device, like your headlights. Then, the current goes through a ground wire secured to the vehicle’s frame. Finally, the current completes its loop back to the power source (- battery terminal).

3 Main Auto Electrical Systems In Combustion Engines

Now that we know more about how auto electrical systems & circuits work let’s look at 3 main areas that use electricity.

Starting & Ignition System

The starting system of internal combustion engines needs to convert electrical-energy from the car battery into mechanical-energy. The ignition system utilizes both electrical and mechanical components. Basically, the starter solenoid, which is an electromagnet that controls the electrical current from the battery turns on the starter motor.

Once the engine has started, the starter motor no longer relies on the car battery to run. Instead, the alternator produces Alternating Current (AC), which powers your vehicle’s electrical systems while the engine is running. Additionally, the alternator converts AC power to Direct Current (DC) and then stores it in the vehicle’s battery to maintain a full charge. 

Auto Lights

Lighting circuits power your vehicle’s auto lights through connections to the car battery. Generally, vehicle lights are wired in parallel (vs. in-series) to provide each light with the right amount of current. Check your vehicle’s owner’s manual for the wiring diagram for your specific make & model. Bare in mind that your automobile’s lighting system is an essential tool for your safety and includes:

• Headlights (High-Beam, Low Beam, Fog)
• Taillights
• Brake Lights
• Back-up Lights (Reverse)
• Blinkers or Turn Indicators
• Hazard Lights
• Running Lights
• Interior Lights (Cabin Lighting)

Auxiliary Systems

Auxiliary Systems are the electrical components that control all the nifty bells & whistles in your vehicle. They may include: 

• Alarm & Security Systems (Automatic Door Locks, Anti-Theft System, Horn)
• Comfort Systems (Adjustable & Heated Seats, HVAC, Sunroof, Window Controls)
• Information Systems (GPS, Instrument Panel, In-car Entertainment, On-Board Computer, Trip Recorder)
• Safety Systems (Side Mirrors, Windshield Wipers & Windshield Fluid Nozzle)

Many of these components are wired to operate whether the car is running or turned off. Fortunately, most of these components draw very little power from the car battery. However, to avoid draining your battery, limit the use of the entertainment systems while the car is not running.

Issues & Troubleshooting

The electrical systems & circuits in your vehicle are complex, and issues can happen at any point. Therefore, check your vehicle’s owner’s manual for a diagram of the malfunctioning electronic component. There are four common circuit issues that could cause an electrical part to fail.

Open Circuit

An open or broken circuit can be a broken wire, loose connection, or corrosion at a connection point. Consequently, an open circuit stops the flow of energy, causing the component to stop operating.

Electrical Short

Electrical shorts occur when the energy flow gets diverted to the ground instead of flowing through the circuit. For example, grounding happens when the wire casing is damaged or broken, and is consistently contacted to a metal object. 

Intermittent Electrical Short

Sometimes the energy flow only gets periodically disrupted, this is called an intermittent short. For instance, the electricity may get diverted from the electronic component through motion or over-heating of the wire.

Overloaded Circuit

An overload is when an electrical component draws more power than usual due to additional strain or malfunction. Therefore, an overloaded circuit will usually blow a fuse, causing the part not to work.

Auto Electrical Systems Repairs & Maintenance

Troubleshooting the electrical system can be time-consuming without the proper tools and training. At Ron’s Garage, we use state-of-the-art diagnostic equipment to diagnose your vehicle’s electrical system. These tools allow our experienced technicians to target the necessary repairs and get you back on the road.

Schedule Auto Electrical Systems Service

Call Ron’s Garage today at (734) 961-4701 or visit us online to schedule your appointment for your auto electrical systems service. 

Previous Blog: Auto Electrical Diagnosis Part 1: System Overview

In Part 1 of this blog series, we introduced the basics of auto electrical systems and identified the most significant components. We also touched on common circuit malfunctions and how to diagnose them. Finally, we offered recommendations for general electrical systems maintenance.

Next Up: Auto Electrical Systems Part 3: Fuses

In Part 3 of this blog series, we will explore Fuses and Fuse Boxes. We will explain what they are, where they are located, and how they work. We will include information on how to troubleshoot common problems and suggest proper maintenance of your vehicle’s fuses.

The post Auto Electrical Systems Part 2: Systems & Circuits first appeared on Ron’s Garage Ann Arbor Auto Repair.

Combustion Engine: Auto Electrical System & Circuits

These days, almost every new car feature and automatic controls rely on its electrical system. Every electric-powered component in your auto works because of an electrical circuit. A circuit is simply a loop of wire that connects the part with the power source (the battery or the alternator). Consequently, electricity continuously flows when the component is in use. Most auto circuits supply power to more than one component. A few of the most common electrical features in today’s vehicles are:

• Air conditioning
• Anti-lock braking
• Digital gauges and lights in the dashboard
• External & internal lights
• Navigation system
• Power door locks
• Power/heated seats
• Power steering
• Power windows
• Stereo system
• Windshield wipers

Auto Electricity: The Power of Three

The three main parts of your car’s electrical system are the battery, alternator, and starter motor. In addition, a complex web of circuitry and switches provides the pathway for every electrical component in your vehicle.

Battery

The battery is probably the most essential element in your vehicle’s electrical system. Without it,  the simple act of starting your car, turning on the lights, or using the power steering are but a dream. Fortunately, one of the battery’s main roles is to provide power to the starter motor, which then activates the engine’s spark plugs. Another is to give power to the peripheral electrical systems (i.e., interior & exterior lights, stereo, etc.) even while the engine is not running.

Alternator

The alternator produces the electricity needed to power your vehicle’s electrical systems while the engine is running. It has an attached belt, which converts kinetic energy into electricity. The alternator converts an alternating current (AC) to a direct current (DC) before storing it in the vehicle’s battery. Furthermore, it  constantly recharges the battery and provides power to electrical features like lights and wipers. This also ensures the battery will have enough  stored energy the next time you want to start your car.

Starter Motor

The starter motor has one significant job. The battery sends a considerable amount of energy to the starter motor when you start your car. The starter motor ignites the compression of air and fuel in the engine cylinders and powers the spark plugs. The vehicle’s engine will not start if the battery or the starter motor fails.

Fuses & Fuse Boxes

The  wiring of your auto’s electrical circuits are protected from overloads or shorts with fuses. Still, they can only handle a certain amount of amperage. Unfortunately, an electrical short or overload could cause a power surge and endanger the entire circuit. However, most fuses have a delicate metal filament that not only maintains the circuit and breaks to open the circuit. Your car’s fuses are conveniently located together in fuse boxes.

Most cars have two fuse boxes. One is usually located in the engine compartment. It manages circuits for electronic drive features, like anti-lock brakes. Look for the second box in the glove compartment or under the vehicle’s driver’s side dashboard. It holds fuses for the circuits that control the passenger compartment devices, such as the windshield wipers, stereo, and power windows.

Engine Control Unit (ECU)

Most modern Automobiles have an engine control unit (ECU), sometimes called an Engine Control Module (ECM) or Powertrain Control Module (PCM). The ECU is basically a mini-computer connected to various engine and fuel system sensors. The ECU is responsible for many tasks, including:

• air-fuel mixture in the engine
• valve opening timing
• ignition sequencing
• engine idle speed
• other essential drive functions
• maximize energy efficiency & power

If the ECU malfunctions or fails, your vehicle may be completely un-drivable. Newer cars are more prone to malfunctions with their ECU, since it runs most of their fuel system sensors.

Common Circuit Malfunctions

Get your vehicle inspected by a technician immediately if you suspect a problem with its ECU or other electronic systems. Any component or function controlled by the ECU is liable to sustain damage unless a qualified technician repairs the system. Your owner’s manual should contain a circuit map explaining which electrical systems operate with each circuit. It can be helpful to reference your owner’s manual when attempting to diagnose a failure in an electrical component.

Auto Electrical System & Circuits Maintenance

You should have your automobile’s electrical system inspected regularly to keep it in good working order. Never ignore minor electrical problems, as they could be symptoms of larger issues, causing serious malfunctions later. In addition, electrical system failures could have disastrous consequences if they occur while driving.

Auto Electrical System Diagnostic Service

Ron’s Garage proudly uses and supports various diagnostic tools, launch scanners, and start testers to diagnose your electrical system. A quick diagnosis can limit unnecessary labor costs. Our skilled technicians utilize electrical and computerized diagnostic measures to determine the source of your vehicle’s issue. This state-of-the-art equipment allows us to narrow down the needed repairs and get you back on the road faster.

Schedule Your Service in Ann Arbor, MI

We would love to hear from you. Call us today at (734) 961-4701 to schedule your appointment or visit us online for all your auto electronic diagnostic service needs.

Next Up: Auto Electrical System Part 2: Systems and Circuits

Our next blog will go into greater detail about your combustion engine vehicle’s electrical systems and circuits.

The post Auto Electrical System Part 1: Overview first appeared on Ron’s Garage Ann Arbor Auto Repair.