Can A Bad Alternator Ruin The Battery?

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Buying a new car battery for your car sometimes means dipping a little deep into your savings especially when this is unplanned.

Waking up one morning and discovering your seemingly okay battery is ruined and requires to be replaced begs the, what are the factors that could ruin your car battery, and is a bad alternator one of such?

So, can a bad alternator ruin the battery? The are alternator is one of the external factors in the car that could lead to the battery getting ruined.

Its condition affects the condition of the car battery. Here in this article, we shall consider how a bad alternator can ruin a car battery, what causes the alternator to go bad, how to know when the alternator or the battery is the issue and the general maintenance of a car alternator.

The car alternator and battery are two crucial components of the car and require each other’s help to work properly.

The battery is responsible for starting the car engine as well as supplying power to other aspects of the electrical system. As the battery runs out of power, the alternator is responsible for recharging it continuously to restore its depleted power.

Therefore, whenever the alternator goes bad, the battery is being continuously depleted without being recharged and will eventually give up at some point.

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How can a bad alternator ruin a battery?

A functioning alternator works in harmony with the car battery, however, when the alternator goes bad, it could ruin the car battery in various ways.

Some of how a bad alternator can ruin a car battery include overcharging the car battery with excessive voltage leading to premature cell failure.

Others include intermittent charging, inadequate charging, and ripple voltage. None of these is seen in a well-functioning alternator.

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What causes the alternator to go bad?

The alternator is a simple car part and can be easily replaced when it goes bad. The known causes of alternator failure are easily preventable if one desires to prolong the alternator life span. 

The alternator can be prevented from performing optimally by the accumulation of dust, dirt as well as oil in the alternator’s electrical windings. While servicing the car, the alternator can be cleaned out properly and this dust removed.

The tension of the alternator belt is also one of the leading factors that can cause the alternator to go bad. When the alternator belt is under higher tension than normal, it may ruin the alternator bearing by pushing them inside. This will cause the alternator to go bad. This happens commonly overnight.

How long will the car run with a bad alternator?

Even when the alternator is bad and fails to recharge the car battery, the remnant charge in the battery can keep the car running for a variable time duration. What are the factors that determine how long the car battery can keep the car running with a bad alternator?

There is a designated time duration for how long a given car battery will be able to keep the car running when the alternator goes bad and fail to recharge the battery, however, the time duration depends on several factors some of which include the amount of electronic load placed on the battery, the type of engine in the car and whether the car is a modern version or not.

In terms of electronic load placed on the car battery, let’s say the car is been driven at night, necessitating the use of the car headlights, this increased load on the car battery will cause the remnant charge to be dissipated more quickly and the battery to become dead in a short period.

Another factor that explains how long or short the battery can run with a bad alternator is the age of the battery. The older the battery the weaker it becomes.

Therefore, older batteries cannot last long without the alternator constantly recharging them. When compared to a new battery, old batteries die off momentarily when the alternator goes bad while driving.

The type of car engine will also affect how long the battery will last. car engines not requiring much electrical supply will allow the battery to last long after the alternator goes bad. diesel engines of the old car version are engineered in a way that affords them minimal dependency on the electrical supply.

The engine is responsible for driving the fuel pump and does not make use of sparks plugs for fuel combustion. Such vehicles with less demand from the car battery can therefore run on the battery without a functioning alternator for several hours before the battery runs dead.

In contrast to the diesel engine, gasoline-powered engine cars make use of electrical systems such as spark plugs. These are huge energy drainers and a significant burden on the car battery.

When the battery is not being recharged by the alternator, it is only a matter of minutes before it is run down the battery.

The biggest drain of battery charge is starting the car engine. If the car alternator is bad and cannot recharge the car battery, try to conserve the remnant charge in the battery by not putting the car engine off unnecessarily.

Also, aside from starting the car, the car’s headlight is equally high energy drainage, therefore, except necessary, the headlights should be put off.

If your car alternator goes bad and you wish to prolong how long the car can run with the remnant charge in the battery, then follow these simple tips to do so.

  • To start the car by turning on the ignition key as this will consume almost all the charge in the battery, rather, use a jump-start booster or someone else’s battery
  • Turn off then electrical accessories such as radios, headlights, fan, AC, while driving.
  • Use a trickle charger to quickly charge your battery to full capacity
  • Drive as fast as you can while staying within the speed limit

Signs of a bad alternator

How can one tell which of these two essential car components are when the car starts acting up? With the appropriate testing kits, it is easy to decipher what is responsible for your car problems between the alternator and the car battery.

However, certain manifestations can also indicate an alternator problem without necessarily testing the alternator. Here are some of such.

  • Let us start with the commonest finding in a car with a bad alternator, this is the warning light seen on the car’s dashboard.  While this light may signify many other things, alternator problems are one of the common reasons for the warning light on the dashboard.
  • When the alternator is bad, but the battery has some considerable charge, the car will start easily without hassle, however immediately it is started, the warning light will show up on the dashboard. This could mean the alternator is failing.
  • When an alternator goes bad in a modern car, non-essential power consumers are automatically short down to preserve the battery energy. This will include the car’s AC, ABS, as well as airbags. This way, the remnant power is channeled to where it is much needed- the running engine.
  • Dim headlights during a night drive may be indicative of an alternator problem.
  • Other electrical issues such as flickering of dashboard lights

Signs of a bad battery

The most glaring sign that the battery is the one acting up is that starting the car is usually a hassle. The car never starts on one attempt. When the battery is completely out of charge, that is, flat dead, only a “click” sound is heard when the ignition key is turned on.

The car battery may become dead as a result of an intrinsic problem with the battery and not as a result of a bad alternator.

When a car battery is not charging, it could be due to several reasons. Here are some of the reasons that could explain why the car battery is not charging.

The battery post can become corroded over time and inhibit the battery from getting charged by the alternator. It is crucial to intermittently check the battery post to make sure the posts are not corroded. Also, ensure a tight connection between the posts and the terminals attached to them.

If at any point, the post is noticed to be corroded, start by disconnecting the battery cables attached to the terminals using a wrench.

The posts can then be cleaned thoroughly and the battery cables reconnected appropriately. It is okay to connect the cables at a slightly different sight on each of the posts.

The second battery problem is seen with older batteries. Batteries have a life expectancy and as they get old, they become weaker with each passing day. so, when the battery has served for about 4 to 5 years, its capacity to hold charge begins to decline considerably. 

Whenever a car battery is unable to hold its charge, it should be taken off the car and recharged to full capacity using a battery charger of high quality.

Aside from this, the battery can also be refilled at a repair shop. If it continues to have a problem with holding its charge, then it should be discarded and replaced with a new one.

Can A Bad Alternator Ruin The Battery – Conclusion

Given the cost of a new car battery, the alternator must be kept in a good working state and be maintained regularly to ensure that it doe not develop any fault that could cause it to ruin the car battery.

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