A Dying Alternator Can Make Your Headlights Do Crazy Things

May 1, 2022

If your vehicle’s headlights are doing crazy things like flickering between dim and bright or shining too bright, Pit Shop Auto Repair advises that the alternator may be dying. The alternator generally lasts about 100,000 miles or 10 years. If your automobile is older than this and you still have the original alternator under the hood, the crazy behavior of the lights is an indication that it may be time to replace it. Here are other signs you have a malfunctioning alternator.

Battery/ALT Warning Light

The battery light may illuminate on the dashboard if the alternator is not producing the right amount of electricity. You may also see an ALT light that turns on or a light that spells GEN. Any of these lights are warning you that there is alternator trouble under the hood.

Difficult Starts/Dead Battery

If it has become difficult to start your automobile and your battery is dying frequently, this is a sign that the alternator is malfunctioning and not charging the battery as it should. In this case, the underlying problem is the alternator, not the battery.

Engine Stalling Frequently

The alternator also provides power to your engine’s spark plugs. They need power to generate sparks. If the alternator is faulty, your spark plugs may start to misfire. Unfortunately, when the spark plugs misfire, the engine will stall frequently.

Malfunctioning Accessories

Your vehicle’s accessories also get their power from the alternator. Consequently, they will malfunction or shut off if the alternator is not producing up to 14.5 volts of power. This can include your entertainment system and your GPS.

Strange Growling/Grinding

The alternator may also give you an audible indication that it needs to be replaced. If you hear strange growling or grinding coming from the engine, it’s possible that the alternator is making this noise. This is a sign that the alternator is wearing out from the inside.

The Smell of Hot Electricity

Finally, we mentioned above that the alternator generates up to 14.5 volts of power. A faulty alternator might produce more than that and overload your vehicle’s electrical system. When this happens, you may smell hot electricity in the engine.

Pit Shop Auto Repair in Libertyville, IL, is here to help, so call us today. We would be happy to inspect and test your alternator to see if it is going bad. If it is, we will replace it with a new one.

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