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What Is The Battery Charging System?

What is the battery charging system?

The charging system is what keeps your car battery charged. Without the ability to recharge it, your car battery would die, and your vehicle would not be able to perform crucial functions, including starting the engine, turning on lights (headlights, interior lights, etc.), viewing and interacting with screens or simply listening to the radio.

The Parts of a Car Battery Charging System

A battery charging system consists of 4 main parts: the battery, alternator, wiring and electronic control unit.

1. Battery

Rechargeable, your car’s battery houses the electrical energy to start your car. It also powers all your vehicle’s electronic systems and functions when the engine is not running. Battery voltage is measured in Cold Cranking Amps (CCA). Every vehicle has a minimum CCA requirement for proper function.

2. Alternator

Driven by a belt, your alternator converts the mechanical energy from the engine into electrical energy, recharging your battery and powering the majority of your car’s electronic components when the engine is running.

3. Wiring

Wiring provides the path for electricity to flow to different electronic components of your vehicle, delivering power to them. This includes the dashboard, interactive screens, mechanical seats, mirrors, windows, lights and more. Wiring also enables the battery to be recharged by the electrical energy generated by the alternator.

4. Electronic Control Unit (ECU)

The electronic control unit (ECU) is the “brain” of the vehicle, controlling most of your car’s functions. The ECU detects when your battery needs to be charged and tells the alternator when to recharge it. Since this computer requires electricity to operate, it’s important to make sure your entire battery charging system is working properly.

5. Fuse Boxes

Your vehicle has two fuse boxes, one under the hood and one by the driver’s seat. These boxes contain fuses that fail if amperage gets too high, allowing you to replace a fuse instead of the more expensive component it was protecting.

Common Battery Charging System Problems

Here are some of the top signs your car’s battery charging system may require service:

  • Engine will not start
  • Blinking or steady battery light on your dashboard
  • All/some electronic components are not working

Want to get your battery and charging system checked? Schedule a charging system check or an alternator test at your local Big O Tires store today.

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