The Alternator: Common Problems & Solutions

Your car uses an alternator to tap into an enormous amount of energy generated by your engine to create its own electricity. Think of it like a hydroelectric dam: it takes advantage of an enormous amount of pre-existing movement to create its own power.

Without it, you would soon need to pull your car to the side of the road as different systems began shutting down.

If you believe your car may have been sold to you with a defect, reach out to us at 833.422.7529 for a free consultation and we will investigate the problem.

The Alternator’s Responsibilities

A general misconception is that car batteries power the electrical components in the car. But that’s far from the truth. The battery’s primary responsibility is to help the car start. After that, the alternator generates the majority of electricity needed for your lights, dashboard, and other components.

Here’s how it works: when the engine runs, it spins a belt attached to the alternator. This then turns the alternator, which essentially contains an electromagnet—making it a sort of generator. The electricity feeds into the rest of the car, including the battery.


Problems with the Alternator

Under the right conditions, an alternator should last between 8-12 years, or about 100,000-150,000 miles. Warning signs that there are issues with the alternator include:

  • Control panel lights dimming when the engine is idling
  • The battery indicator illuminates, or you see “Alt” (alternator) or “Gen” (generator) on the dashboard
  • Strange smells coming from under the hood (burning rubber could be a sign there’s an issue with the serpentine belt)
  • Strange sounds coming from under the hood (grinding or whirring may indicate the belt is coming off or something is wrong inside the alternator)

Watch for these warning signs at all times. Ignoring even one of them could leave you stranded on the side of the road, as important components like lights and power steering rely on the alternator. A dead alternator could even stop the car altogether.

Solutions to Alternator Issues

If you jumped your car and it runs for a short time and then loses power, your alternator is likely to blame. If the car continues to run indefinitely without issue, you probably have problems with the battery.

If you think you’re having problems with your alternator, it is time to take your car to your dealer. At the dealership, a technician will typically run a voltage test to see how much electricity is being generated. If there isn’t enough, you will either need to repair the alternator, replace the alternator, or replace the serpentine belt.

Finally, you can also peek underneath the engine to see if the undercover is intact. This blocks water and sediment from the road shooting up and entering the alternator, where it can cause premature wear and tear. If the undercover is damaged, consider replacing it.

An alternator is a generator of electrical electricity in a vehicle and is a primary element of the vehicle’s charging machine. All motors with an inner combustion engine, besides a few hybrids, have an alternator. When an engine is running, the alternator prices the battery and substitutes extra electric powered electricity for the vehicle’s electric systems.

An alternator is bolted to the engine and is pushed with the aid of using a serpentine belt (power belt).

An alternator is a maintenance-unfastened unit. It may remain for as much as 10-15 years with no repairs in a few motors. If an alternator fails, the automobile might also run for a quick time on battery electricity. However, the engine will stall as quickly because the battery price is depleted. Replacing an alternator with a brand new OEM component is expensive. However, there are alternatives. 

How to know the alternator has got issues?

The maximum, not unusual place symptom of a hassle together with your vehicle’s charging machine is a battery-formed caution mild (withinside the image) or the “CHARGE” icon that comes on simultaneously as driving. Usually, this caution mild has to come on while you switch at the ignition; however, it has to disappear quickly because the engine is started. If it remains on, there’s a hassle together with your charging machine. The charging machine caution mild would not factor at once to a failed alternator, although alternator issues are not unusual to place. Your mechanic will want to do a similar checking out to pinpoint the faulty component.

Another symptom of a susceptible charging machine is that sprint lighting fixtures and headlights dim at idle; however, they become brighter while the engine is revved. This hassle might be brought about now no longer most straightforward with the aid of using a susceptible alternator, however additionally with the aid of using a failing battery, terrible connection on the battery terminals, or an unfastened serpentine belt. A whining/humming noise coming from the alternator is any other symptom of alternator troubles. In a few motors, it can be as a result of a loud alternator bearing. In a few Jeep/Chrysler vehicles, a terrible alternator decoupler pulley ought to motivate the identical noise.

How to test the alternator?

Your mechanic can look at the nation of your charging machine with the battery and charging machine tester (withinside the image). A battery and charging machine take a look at (AVR take a look at) expenses from $30 to $50. The look will display if the charging machine is susceptible or is now no longer running at all. It also can come across if one of the diodes withinside the alternator has failed.

If the charging machine fails to look at it, your mechanic will want to do a similar diagnostic to peer if it is the alternator or something else inflicting the hassle. Other charging machine issues include an unfastened power belt, defective wiring or blown fuse, faulty ignition switch, etc. 

If no charging machine tester works, your mechanic can do an easy diagnostic. It entails checking the battery voltage with the engine off and with the engine running. The battery voltage has to boom as soon as the engine starts because the alternator has extra electricity. If the battery voltage no longer booms as soon as the engine is started, there’s a hassle with the charging machine.

Alternator rebuilding vs replacement

Replacing an alternator expenses from $350 to $520 with an o.e.m component. OEM alternators from a provider are more expensive. Another opportunity is to have your alternator rebuilt. The manner it works is your mechanic can get rid of the alternator and ship it to the closest alternator/starter rebuilding shop.

Once the alternator is rebuilt, your mechanic will defloration it back. It might also take more significant time. However, it is typically cheaper because you simply pay the price to get rid of defloration ($70-$120) plus the rebuilder’s price ($80-$150). 

Rebuilding an alternator at home is hard and takes numerous times, however now no longer impossible. Alternator rebuild kits are available online for $15-$50.

Whenever the alternator is changed, it is an excellent concept to alternate the serpentine belt too. It isn’t always costly, and with the aid of changing it collectively with the alternator, you could save on labor because the serpentine belt needs to be eliminated to update the alternator. Read more on the serpentine belt.


Whenever the alternator is changed, it is an excellent concept to alternate the serpentine belt too. It isn’t always very expensive. With the aid of changing it collectively with the alternator, you could store on labor because the serpentine belt needs to be eliminated to update the alternator. 

How an alternator lasts longer than usual

Often an alternator fails in advance while a defensive engine undercover or guard is broken or missing. This occurs due to the fact water splashing from the street receives withinside the alternator and causes it to put on faster. If your engine under shield is broken, have it changed to hold the engine compartment smooth and dry. A coolant or oil leak also can harm the alternator. Similarly, when cleaning the engine compartment, the alternator needs to be blanketed with water and detergent. This is how one can help the alternator to work smoothly and keep working well for years.

How an alternator works

A regular AC vehicle alternator has a stator (desk-bound outdoor winding) and a rotor (rotating internal winding). A voltage provided through the voltage regulator to the rotor winding energizes the rotor and turns it right into a magnet. The rotor is turned around with the aid of using the engine through a power belt.

The magnetic discipline produced using the rotating rotor induces AC electric powered modern withinside the desk-bound stator winding. Diodes are used to transform AC modern into DC modern used withinside the vehicle’s electric powered machine. The output voltage is managed with the aid of using the voltage regulator (image below). Typically, a voltage regulator is integrated into the alternator.

The maximum, not unusual place alternator issues consist of worn carbon brushes (the 2 “legs”), worn touch rings (the two copper cylinders in the back of the rotor withinside the cutaway pictograph), and a failed voltage regulator.

Bad outer and internal alternator bearings (vast and miniature silver cylinders withinside the cutaway pictograph) can produce a whining noise. When the alternator is rebuilt, the bearings, voltage regulator, brushes, and different elements are generally changed with new ones.


What are the constraints of the alternator?


Charging a lifeless or low battery is the simplest process of plugging in the battery charger simplest!

As said above, an alternator is designed to hold the price of a battery.  Due to the significant electricity necessities of the regular operation of a motor’s electric machine these days, the alternator typically runs at or close to its most output the whole time the automobile is pushed.  A lifeless or low battery provides the paintings the alternator is needed to do.  There truly isn’t any manner for the alternator to recharge a low or lifeless battery and electricity the electric machine at an identical time.

Improvements in alternator layout over the years

While it’s accurate to mention that the fundamental ideas of the alternator are identical these days as they had been while the primary alternator was designed, many specifics of alternator layout have been modified considerably.  The quantity of strength required to run an electric motor machine these days is three instances of what it turned into in advance. In the 1970s, the everyday most electricity output of an alternator for a totally loaded vehicle turned into rated at approximately fifty-five to 60 amps.  Today, the most output score is drawing near 150-a hundred and sixty amps even though the alternators themselves are simplest, barely bodily larger than their predecessors. This fulfillment of significantly growing strength output while keeping a noticeably compact length and weight is impressive.  Some alternator producers have managed to do that at the same time as genuinely growing the existence span of the alternator.  To perform this, they’ve improved (1) fan designs for higher cooling, (2) rectifier and regulator designs for extended durability,(3) and stator layout to maximize the quantity of cord that may be in shape into the alternator.  Modern alternators use two inner lovers connected to the rotor to flow into the air through the alternator.  Another easy issue is that more recent alternators spin at better speeds than ever before.  With this approach, the lovers can move more significant air for cooling. This additionally helps the usual boom output, considering that a part of an alternator’s strength output is a feature of how speedy it spins. For more information and updates on this and different thrilling matters, you could contact us, and we will do our best to answer your queries in another article on the alternator.

Avoiding Repeated Alternator Problems

If you have constant issues with the alternator or electrical systems in your car, you may have been sold a lemon. Robison Lemon Law Group can help you navigate both the Magnuson-Moss Warranty Act and lemon laws to ensure you receive the justice you deserve. Our experienced legal team will work with you to ensure you receive the compensation you deserve.

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