How to Hook Up an Alternator

The alternator basically acts as the brain for the battery. Without a good alternator, the battery will not stay charged. This means that everything that runs off the battery will not work at all until a new alternator is put in. Basically you cannot drive your car without a good alternator. You can get a used alternator at any junk yard where they sell used parts or you can get a brand new alternator at any auto store. Depending on how handy you are with working on cars, you might need another person to help unhook the old alternator and put the new one in. Even if you are great with working on cars, it still might be a good idea to have someone help you just in case something goes wrong.

Things You'll Need

  • Alternator
  • One socket
  • One ratchet
  • Car jack
  • Jack stands
  • One other person if you think you need the help

Taking out the old alternator and putting in the new alternator

  • Disconnect the battery from the battery cables. Jack up the car on the front passenger side and place jack stands to keep it up. Since you will be working underneath the car, it helps to keep the whole front end elevated so the car does not fall on you.

  • Remove the tire and then the serpentine belt. There should be a spring loaded tension wheel on the serpentine belt, push on this and it should come off easily. The serpentine belt is the belt that keeps everything in the motor on the car running right. The serpentine belt also keeps the battery charged. Once the belt is off you will then remove the old alternator. You might need one other person to help you but it is not necessary. If your car has individual belts instead of a serpentine belt, the alternator should be on a slotted bracket. Loosen the bolt on the brackets and the alternator should move so you can remove the belt.

  • Remove the old alternator. Sometimes the alternator is way down in the motor so you might need to remove a few other things on the motor. Bolt the new alternator in and make sure the bolts are snug. Plug the hot and ground alternator wires into the starter. The alternator wires keep the battery charged and keeps the headlights and windshield wipers running. Double check to make sure the alternator wires are hooked up right. Reconnect the battery to the battery cables.

  • Replace any other parts you might have had to take off in order to get the old alternator out. Put the serpentine belt back on. Put the tire back on and start the car. Now you have your new alternator in and you're ready to go.