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How To Tell If Alternator Is Overcharging?


How To Tell If Alternator Is Overcharging?

The alternator is a component powered by your car’s engine. Its main job is to keep the car battery recharged, so it’s ready to deliver the necessary cranking power to start your vehicle the next time. Unfortunately, it can cause an overcharging, silent, but potentially damaging condition.

You can tell if your alternator is overcharging by looking out for its indirect symptoms. For example, the battery or alternator warning light will illuminate on your dashboard. Besides that, fuses and light bulbs will blow more often than usual. New batteries that fail quickly, or existing ones that overheat, have physical damage, or have high voltage readings are also clear signs of the same problem.

Read through this guide to understand the symptoms that point to an overcharging alternator. The sooner you spot the problem, the more damage you can prevent to your car’s electrical system.

What Are The Symptoms Of An Overcharging Alternator?

The most challenging thing about an overcharging alternator is that there is no clear and immediate sign of a problem. As a result, the overcharging condition will continue for a while until you notice one of the many symptoms it triggers.

Here are the symptoms you must look out for to know when your alternator is faulty and overcharging the car battery:

1. Warning Lights Or Indicators

A warning light or indicator on your instrument panel is the first hint that your alternator is overcharging. That indicator typically takes the shape of a battery logo. However, some car models have one with the word ‘ALT’ (short for ‘alternator’) instead.

Naturally, many battery and alternator problems can trigger those indicators to light up on your dashboard. 

One of them is an overcharging condition, so you should troubleshoot your alternator as soon as you see the warning light turn on.

Read: What Are the Symptoms of a Bad Alternator?

2. Fuses And Lights Often Blow

Another way to tell if your alternator is overcharging is by tracking how often you replace fuses and light bulbs.

It’s only normal for those components to fail or ‘blow’ after extended use. However, if you find yourself replacing them unusually often, you must troubleshoot your alternator.

An overcharging alternator sends too many volts into the car’s electrical system.

Fuses are sacrificial devices that will destroy themselves when there’s too high a voltage in the system. Doing so protects the overall electrical system from damage.

Besides, having light bulbs that fail too often is also a sign of the same issue.

Read: Can You Jumpstart a Car With a Bad Alternator?

3. High Voltage Reading

A car battery with a high voltage reading is one of the most direct signs of an overcharging alternator. Naturally, you’ll only find that out if you have a voltage meter or a multimeter that you can use to test the battery.

Under normal conditions, you’ll find a car battery measuring between 11.7 and 12.6 volts while the engine is off. However, when you start the engine, that voltage will go up to as much as 14.8 volts.

Anything above that number clearly indicates that your alternator is faulty and overcharging your car battery.

4. New Battery Fails Soon After Replacement

Next, you’ll want to consider how often you’ve changed your car battery. A standard battery will wear out after 2-4 years under regular use. As it reaches the end of its lifespan, the battery will lose its ability to hold an electrical charge.

You’ll experience issues like flat batteries or problems starting your vehicle.

Suppose you recently changed your car battery, yet you’ve discovered that it no longer works, and you must get a new one. In that case, your overcharging alternator is likely the cause.

An overcharging condition will cause a battery to experience excessive wear. Unfortunately, that problem can be severe enough to destroy a brand-new car battery months after you’ve installed it.

Read: What Causes Electrical Problems In Cars, And How To Troubleshoot Them?

5. Physical Damage On The Battery

You can tell if your alternator is overcharging by inspecting the car battery up close. You can do this by lifting your hood and using a flashlight to look for physical signs of damage.

Alternatively, you could remove the battery and look closely at it on a well-lit table.

Some of the signs you’re looking for include the following:

  • Seeping or leaking battery fluid
  • Bulging or swelling on the battery case
  • Curved surfaces on the battery
  • Excessive water loss in flooded batteries

Read: 3 Signs That Your Car Needs a New Battery

6. Overheating Battery

Last but not least, an overcharging alternator will cause your battery to overheat.

Car batteries usually generate some heat when charging or discharging. That’s thanks to the chemical reactions happening within, which produce heat as a byproduct.

On top of that, the battery will also feel warm to the touch when surrounding temperatures are warm. So, for example, you’ll notice your battery being warm during the hot summer months.

However, suppose your battery is overheating and hurts your hand when you touch it. In that case, that means it’s being overcharged by the alternator. That can be pretty dangerous, so it’s best to disconnect the battery immediately and troubleshoot the alternator further.

Read: Symptoms Of A Bad Crankshaft Pulley

Can You Drive With An Overcharging Alternator?

No, you should not drive with an overcharging alternator, even if your engine can start and run normally.

The reason for this is straightforward. When your alternator is overcharging, it’s actively causing damage to the car battery. As you read above, that will lead to battery bulging and leaking battery fluid, which is incredibly dangerous to you and your passengers.

Besides that, every moment your car engine runs with an overcharging alternator, the voltage in the electrical system is running too high. That will quickly cause damage to electrical components like wires, fuses, lights, and more.

Your best bet is to leave your car where it is or get it towed to a workshop. That way, the alternator can be fixed or replaced (as needed) without causing further damage to your car’s electrical system and components.

What Do You Do If The Alternator Is Overcharging?

When your alternator is overcharging and causing damage to your car’s electrical system, replacing it with a brand-new one is the most practical solution. That way, you can rest assured that the new alternator will work correctly and won’t cause any problems you’ll have to deal with anytime soon.

The alternator is directly powered by the engine, so you’ll find it under the hood. You’ll find it near the engine because it shares its serpentine belt and gets its power there.

Remember that the alternator is not the car part you’ll have to change often. Some cars even go through their entire life spans without any alternator problems.

So, if yours is failing, replacing it with a high-quality spare part will keep your car running and give you plenty of peace of mind in the years to come.

Final Thoughts

For many people, the alternator is an easy part to overlook. That’s because you won’t notice it until it starts to cause you trouble. An overcharging condition is one of the problems that an alternator will cause you when it fails.

So, suppose you notice one or more of the symptoms described above. In that case, you must troubleshoot the alternator and rule it out as quickly as possible.

If the alternator is to blame, install a high-quality replacement to keep your vehicle in excellent working condition.

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