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Do I Need a New Alternator?

Do You Need a new Car Alternator?It’s probably happened to you before. You go to start your car and nothing. Maybe the lights on the dashboard come on for a second but then, nothing. You’re left with a dead battery. It’s no surprise, in the Southwest car batteries only last about three years—if you’re lucky. Your car may even go through several batteries before ever needing a new alternator. In some cases though, the cause of a dead battery is due to a failing alternator. 

The trouble is, how do you know which component of the charging system is at fault? Learn how alternators work and the subtle symptoms that tell you that the alternator has lost its luster. 

How the Alternator Works

The alternator is connected to the front on the engine and is powered by the crankshaft by the serpentine belt. It’s just one of three components that create and provide electrical energy in your vehicle. An alternator transforms electrical energy from mechanical energy with an alternating current (AC) to help keep the battery charged, power electrical modules such as power windows and locks, and supply power to the vehicle’s internal computer. The alternator is a metal housing that contains the following components to generate power:

  • Stator & Rotor – Magnets that revolve to create the alternating current that is converted into electricity.
  • Diodes – Transform alternating current into a one direction current to charge the battery.
  • Voltage Regulator – Regulates voltage to prevent power surges.
  • Cooling fan – Helps to dissipate heat generated while creating energy to protect internal components.

Battery or Alternator?

A failing alternator can take down a perfectly good battery. The alternator is meant to send power to the battery but is unable to revive a battery that is weak or that is already dead. Many vehicle owners in these situations find themselves asking, “do I need a new battery or alternator?” You can determine which component is the guilty party by running your own test with jumper cables. Begin the test by jump starting your vehicle. Immediately remove the cables. Does the car stall or continue running? If it stalls immediately, the alternator is most likely the offender. On the other hand, if the vehicle continues to run after about five minutes, the battery is likely at fault. 

How Do I Know If I Need a New Alternator?

Some alternators can survive for up to 100,000 miles in ideal conditions, however, in areas with extreme heat or cold, the timeline may be reduced. An alternator that is on the verge of failure may struggle to start or the headlights may dim or flicker. If your vehicle’s alternator is exhibiting any of the symptoms below, be sure to have a technician test the electrical system to determine if it’s time to replace the alternator:

  1. Unusual Sounds: Whining or grinding sounds could be an indication of failure from the bearings, the stator and rotor, or other components that are spinning inside the alternator.
  2. Foul odor: A smell of burning rubber can indicate that rubber belts are not rotating properly, creating friction and heat which causes the rubber to burn and produce a foul-smelling odor.
  3. Battery Light Illuminated: Your vehicle is equipped with all kinds of sensors and modules that send data and messages to the vehicle’s internal computer. When an abnormality is detected in any given system, the internal computer illuminates the coordinating light on the dashboard. If your vehicle’s alternator is in failure, the battery shaped symbol, the letters ALT or GEN, or the check engine light may come on.
  4. Powerless Electrical Devices: While you may notice dim headlights or dimmed dashboard lights, you may also notice that power components such as power seats, windows, windshield wipers, and other electrical components are sluggish. You may also notice the radio, or the touchscreen is inoperable.

Call Upon the Experts

The electrical system in a car can be rather complicated and should be handled with extreme caution. Long term damage could be caused to the vehicle by an unknowing DIYer. While jump starting your car to test the battery or alternator or tightening the serpentine belt are acceptable to perform on your own, repairing or replacing a failed alternator is best left for the professionals to handle. 

At Sun Auto Service, we have some of the best professionals in the business serving Nevada and Texas. Whether your battery has died catching you by surprise or your car is presenting symptoms of a failing alternator, we can help! We offer a free battery test to check the status of your battery. We can also measure the voltage of the alternator to determine if the alternator is producing enough current to further isolate the issue. And because we know you’re busy, in most cases repairs can be completed the same day. Sun Auto Service is prepared to handle all your automotive needs. Give us a call or stop into any of our many locations today!