All About the Alternator in Your GMC Vehicle

The alternator is powered by the engine via a pulley. Its purpose is to power the electrical system and charge the battery when the engine is running.

The Alternator Explained in Simple Terms

GM Alternator

The alternator basically has four components:

  1. Rotor: a rotating set of copper windings that is connected to the alternator pulley.
  2. Stator: a stationary set of copper windings that convert the rotor’s magnetic field into alternating electric current.
  3. Diode: a semiconductor designed to convert alternating electric current to direct electric current.
  4. Voltage regulator: a component that limits the voltage going to the battery to prevent overcharging.

In a nutshell, the alternator takes mechanical power from the engine and converts it into direct current (DC). The DC current powers the vehicle and charges the battery.

Why is an Alternator Necessary to Power Your Car?

The car battery needs to be charged. The alternator provides the electrical current that charges the battery. If the alternator fails, the battery will use its stored electrical energy until there is none left.

Without the alternator continually charging the battery there will be reduced electrical power. You will notice dimmer headlights, slower power windows. The battery will eventually drain and the engine will not be able to start at all.

That’s why it’s important to monitor your alternator with a voltage meter, and then replace it as soon as you confirm that it’s failing.

Can an Alternator be Replaced at Home?

Alternator location

Image Credit: Paul Michaels

Yes, you can replace an alternator at home as long as you have the right tools. In fact, it’s much cheaper than paying a shop to replace the alternator for you. The basic overview of the process is as follows:

  1. Order an OEM replacement alternator from us at a discounted price.
  2. Disconnect the power cable and control harness attached to the old alternator.
  3. Remove the old alternator.
  4. Install the new alternator.
  5. Reconnect the power cable and control harness to the new alternator.

The repair should take you about an hour or two, depending on your level of expertise.