Can Bad Alternator Drain Battery? How to Fix a Bad Alternator?

The performance of the battery as well as the alternator is very important to the ignition system of a vehicle. The battery is responsible for turning the engine on and supplying power to the vehicle’s electrical components; however, the alternator is the component that is responsible for recharging the battery whenever the engine is in operation by converting mechanical energy into an electrical supply.

If your alternator is malfunctioning, you can discover that the repercussions are expensive. Because the batteries are not being charged while the car is operating, the vehicle will come to an abrupt halt as soon as the battery is completely depleted.

You won’t only run into that one problem, however; there will be others. In a vehicle with a faulty alternator, the battery might discharge even while the engine is turned off.

Can bad alternator drain battery? How should an alternator be tested? When an alternator isn’t working properly, what happens to the battery? What causes a car battery to drain? This article is an absolute must for you to read if you’re trying to find the answers to the questions above.

How To Know If Your Car’s Alternator Is Draining the Battery?

If you are experiencing issues with the operation of your vehicle, you should be concerned about the batteries and the alternators. But how can you know if the alternator is malfunctioning, and how can you test to see whether the alternator is causing the battery to run down?

There are two ways to determine whether or not the alternator is faulty and causing the batteries to run down.

The first examination may be carried out in your garage. You have to make sure the hood is up as you start the vehicle. The next step is to disconnect the negative battery terminal connector from the 12V battery while the engine is still running.

If the engine suddenly stops running, the problem most likely lies in the alternator. Because the batteries are unable to provide the engine with sufficient current to keep it operating on its own, the batteries are being depleted.

The second approach is the one that is used by the majority of people when evaluating alternators to determine whether or not they are in healthy condition.

However, in order to have it analyzed, you will be required to remove it from the vehicle. When you have finished connecting the alternator to a terminal, the voltage scale ought to indicate anywhere between 12 and 13.5.

Any number lower than that implies that it is not capable of fully charging the battery. On the other hand, if the reading is higher than that, it means that the 12V battery is being charged too quickly. In either scenario, it shortens the amount of time the battery may remain charged.

Signs of A Bad/Faulty  Alternator

You are now aware that a malfunctioning alternator poses a risk to the general performance of the vehicle, as well as to the batteries, other electrical components, and electrical current. But how can we tell whether the battery in our car is being drained by the alternator? Alternator failure may be identified by a number of warning signs that indicate its condition is deteriorating.

The following symptoms should present themselves if the alternator in your vehicle is malfunctioning:

  • If your vehicle starts easily yet the warning light on the dashboard turns on immediately, the issue is not with the batteries but rather with the alternators in your vehicle.
  • If you are traveling at night and notice that the headlights are not as bright as usual, you should not assume that the battery is at fault but rather the alternator.
  • If you observe that the brightness of the lights on the dashboard progressively decreases while the vehicle is being driven, the problem is probably caused by the alternator which is not functioning properly.
  • If it is overheating, you can notice a smell similar to that of burnt rubber.

What is the Cause Behind a Bad Alternator?

There are a few factors at play that contribute to an accelerated rate of alternator failure. You have a chance of preventing it if you are aware of the reasons. The following are the primary causes:

  • An alternator belt that is overly tightened. The component could be held firmly, but the bearings of the electromagnetic system might be damaged as a result.
  • Over time, dirt, dust, and oil will accumulate. The presence of these particles prevents the alternating machine from functioning at its best potential. Living in a polluted location increases the likelihood that you may experience the issue frequently.

By doing routine maintenance on your car, you may eliminate the factors that might ultimately lead to a dead alternator. Check the drive belt tensioner to ensure that it does not remain in an excessively tight state. To keep the dust at bay, you should also make an effort to clean the car whenever you have the opportunity to do so.

How To Fix A Bad Car Alternator That Is Draining The Car Battery?

You may choose to fix an alternator yourself, or you can go to a repair shop for assistance. If you have the serpentine belt diagram, the method of appropriately reinstalling the belt is easy. However, if you take your vehicle to a repair shop, the cost of replacing an alternator might be rather high.

The dead vehicle battery, the malfunctioning alternating device, and the serpentine belt need to be detached from each other. Then, remove the device’s bolts gently, and eliminate any wiring connections that are still attached. Now, reinstall them in reverse, and might see the alternator issue fixed.

Effective Tips for Longer Driving While Your Car Has A Bad Alternator

How long Does a battery last with a faulty alternator?

The correct response varies based on the model of the vehicle’s engine, the vehicle’s age, and the number of electrical components it contains. Due to the straightforward nature of the traditional diesel engine’s operation, it is possible for the engine to continue functioning for a number of hours despite the presence of a faulty diode.

Again, due to the presence of spark plugs that deplete the battery more quickly, modern hybrid vehicles and patrol cars may only have a range of around half an hour.

Here are some suggestions that can help you run for longer even while your alternating machine has gone bad.

  • While starting the engines, you should consider using a jump-start booster.
  • While you are driving, make the most efficient use of the features in your vehicles, such as the headlights, the fan, and the radio.
  • When you drive at a quicker speed, you are able to go farther in less amount of time. However, you should never go beyond the speed limit.
  • Make the switch to LED lightbulbs, which consume less power.

Frequently Asked Questions

What Is a Key-Off Battery Drain?

What might cause a car battery to deplete even while the vehicle is not being driven? Even after the engine is switched off, numerous electronic components, such as radios with preset stations, timers, and security alarms, continue to take power from the vehicle’s batteries. A Key-Off battery drain, also known as a parasitic drain, refers to the accumulative load that depletes the battery.

What Is an Alternator Exciter?

Exciters are mini generators that are positioned on the same shaft as the alternators in order to produce a magnetic field that is always in motion in a stationary position.

What happens to the radio if I have to disconnect the battery?

When the batteries are removed, all of the electrical components, including the radio, the clock, and the headlights that dim, lose their power. When you reconnect the batteries, you will need to first reset the clock and then input the radio code before they start working again.

Will a bad alternator diode result in a parasitic drain and still charge the battery?

A parasitic drain on the battery might be caused by faulty diodes or alternators. However, it continues to charge the battery even while the engine is running, and it continues to do so until the battery is entirely depleted and makes some unusual sounds.

Can a faulty alternator drain the battery when the vehicle is off?

Even when the engine is turned off, a faulty alternator diode will continue to take current from the battery. It’s possible that when you go to start the automobile in the morning, it won’t start.

The Bottom Line

Indeed, it does, and it is one of the primary factors that contribute to the battery losing its charge. In the event that you see any of the symptoms outlined above, it is imperative that you have an alternator test performed on the engines before it is too late to prevent the battery from dead.

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