Signs You May Need to Replace Your Alternator

How do you know your alternator needs replacement?

It is not uncommon for an alternator to fail with little or no warning however there may be some signs that indicate that it might be on its way out.

Signs your alternator might be failing

In some cases, there can be some warning signs that indicate that your alternator is about to die.  Quickly identifying these signs can save you from being stranded on the side of the road.

A common sign of a failing alternator is that the headlight beam will pulsate from dim to bright.  This indicates that there is an inconsistent current being generated.

Some alternators may also stop working or emit a squealing sound if they are charging several electronics or accessories at once such as headlights, fog lights, seat warmers, and audio system/video players.

More obvious indications that you should have it checked is a burning smell from the engine compartment or an illuminated alternator dash warning light (if vehicle equipped). If either of these are occurring, schedule service today using CarAdvise.

How an alternator works

The alternator is an engine accessory that provides power to and continuously charges the battery along with the vehicle electrical system.

The alternator is considered a hard-working part in every vehicle.  Its primary function is to provide power to the electrical system in place of the battery.  The battery’s job is to start the vehicle and the alternator keeps everything that is electrical and electronic running.

Alternators typically last about seven years or about 100K to 150K miles.  There are other circumstances where alternators may only last about 80K miles.  There are several factors that can affect the life span including the alternator quality, driving conditions, and how many electronics are being utilized.

Maintaining an alternator

There are a few pieces of advice that (when followed) can help to prevent premature failure.

Incorrectly installed accessories can overload the electrical system, resulting in early failure.  So be weary when installing aftermarket accessories.

Fluid leaks in the engine compartment that cause the alternator to become wet can damage the internals of the part.  In addition, a drive belt that is too tight can damage the alternator bearings.

When an alternator goes bad, the electronics will draw power from the battery resulting in failed battery.  This is often misdiagnosed as a failed battery as opposed to a failed alternator.  It is suggested to have an inspection performed by a CarAdvise Certified shop to properly diagnose and repair the problem.

If the battery dash warning light is illuminated, get it checked out by a trustworthy mechanic.  To schedule service with a reliable shop and have your battery/ alternator inspected, use CarAdvise.

When selecting a replacement part with a CarAdvise shop, select a brand name that is accompanied by a good warranty (some may even carry a lifetime warranty).  Just ask your CarAdvise Certified shop mechanic or one of the CarAdvise ASE Certified Advisors for their best recommendation.

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