Can You Jumpstart A Car With A Bad Alternator?

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On your way to the mechanic’s shop, you pull over to take a short nap. As you wake up to continue the journey, the car fails to start.

The continuous clicking sound indicates that the battery is dead. You slot and turn the key again, but the sound doesn’t change.

This time, you know the alternator is bad. The only option left is to jumpstart the car with the faulty alternator and dead battery. How will you go about it?

This article provides insights into how to jumpstart a car with a bad alternator. I have also answered a few questions bordering on whether or not you can drive a car with a bad alternator.

There are also details about the danger of an improper jump starting procedure. Stay connected.

Can You Jumpstart A Car With A Bad Alternator?

The straight answer to your question is yes. It’s easy to jumpstart a car with a faulty alternator.

When your car battery has a little power but the alternator is faulty, you can jumpstart your car. There are two methods you can use to jumpstart a car with a bad alternator.

You can go for a car jump starter or use jump-start cables. They both will help power your car engine to life.

When your car battery is dead, you’ll feel bad. But imagine the component that empowers the battery and brings it to life goes bad! I’m sure your reaction will be worse.

What it implies is that a faulty alternator will cause the battery not to charge. And if the battery is not charged, the car cannot work.

A faulty alternator is a worse enemy than a dead battery, isn’t it? The life or activeness of the battery depends on the alternator.

It means when the alternator goes bad, you’ll need to replace it as soon as possible. In the meantime, you can do a quick fix provided you have a good battery.

How To Jumpstart A Car With A Faulty Alternator

The methods you can use to jumpstart a car with a faulty alternator are pretty safe and simple. But you should follow the rules. You should be done within 3-5 minutes. You should allow the jumpstarted car to run for at least 15 minutes before you start to drive.

Precaution to follow:

  • Keep the two vehicles distant from each other, preferably 45 centimeters away.
  • Never let the two camps touch each other.
  • Locate the positive (+) and negative (-) terminals of the batteries of the donor and recipient’s vehicles.
  • Never leave the keys on the ignition of either vehicle.

Steps To Jumpstart A Car With A Bad Alternator

Supplies needed

  • Battery with a good alternator
  • Clamps or cables

Step 1: Park The Two Vehicles At A Distance

The first step is to pull over the two vehicles on flat terrain and turn them off. While facing each other, the two vehicles must be 18 inches apart. Make sure the battery and alternator of the donor car are good.

Step 2: Connect Cable Terminals

Locate the negative and positive terminals of the two batteries. Connect the positive cable end of the jumpstarting battery to the positive cable end of the car with a bad alternator.

Place the negative cable on the negative terminal of the jumpstarting battery. Needless to say, the positive cable is usually red while the negative is black. Make sure the cables at opposite ends are firm in place.

Step 3: Ground The Negative Cable

Place the opposite end of the black (negative) cable on bare metal or unpainted or chromed frame. You can also place it on a stud. Do not connect the opposite negative end of the cable to the negative terminal of the battery with a faulty alternator.

Step 4: Start Donor Car’s Engine

Once all the connections are in order, you can start the engine of the car with a good alternator. Allow the engine to run for 3-5 minutes at 2000 revolutions per minute.

However, if you’ll be driving the car immediately, allow the engine to run for not less than 15 minutes. The colder the weather, the more time you should allow the engine to run.

Step 5: Crank The Recipient’s Car

As the donor’s car engine is running, try to crank the engine with the faulty alternator. If it cranks, then you can disconnect the cable; if it doesn’t, allow the donor’s engine to continue running

Step 6: Disconnect Cables

Start by dislodging the negative (black) cables on the battery with the bad alternator. Follow this by removing the negative (red) cable from the dead battery.

The third step is to remove the negative (red) cable from the good battery. Lastly, dislodge the positive (black) from the good battery.

Step 7: Replace Bad Alternator

It’s worth saying that the first thing to do is to replace the alternator. When you’ve driven your vehicle to a safe place, look for a mechanic.

They should help you remove the bad alternator and install a new one. I won’t recommend a DIY alternator repair or replacement. A certified mechanic has the experience and knowledge.     

What Are The Signs Of A Failing Alternator?

It’s important to be on the lookout for the signs when your alternator is going bad. This will help you take action as promptly as possible. You can either repair your alternator or replace it, depending on the extent of the damage.

Hard Start

A bad alternator can cause the engine to struggle to start. You may also notice that the engine stalls randomly severally when you try to start it.

The reason is that the alternator is weak to send any power to the spark plugs. The more energy the plugs receive, the stronger it is to trigger the engine to complete the ignition process.

Battery Not Charging

It’s a no-brainer that your car battery will either become dead or not charge when you have a bad alternator. The battery depends on the alternator to stay charged.

Without the battery, no part of the engine will be able to receive power to spark. The far-reaching consequence of a dead battery is an unresponsive engine and a grounded car.

Burning Smells

Another sign to look out for to suspect a dying alternator is a burning smell. The inside of the engine may start to overheat, causing some wires and rubber to burn and produce an unpleasant smell.

Don’t forget, when the alternator fails, the alternator belts will become extremely hot and start to give chemical smells.

Squealing Sound

You should also keep your sense organs on the ground. Some squealing or squeaking sound may be coming from under your car hood as you drive along. Although the causes of this smell may vary, a bad alternator is the main suspect.

Checking Engine Light Comes Up

Almost all major defects in a car cause the check engine light to illuminate. Without a doubt, a bad alternator is an important consideration here.

When the alternator starts to go bad, there’s a likelihood that the warning lights, will come up. This will include a battery-shaped light, an “ALT” light, and a check engine light. They all represent a problem with your alternator.

Can you Drive With A Bad Alternator?

Yes, you can drive with a bad alternator. But if you ask me, this is not a smart idea to consider.

When the alternator or any component of your car gets damaged, it can have a multiplier effect on other parts of the car.

For instance, a broken alternator can interfere with the electrical system of your car. Needless to say, a failing alternator will cause your car battery to drain with little or no charge in it.

In addition, when you drive a car with a bad alternator, you’ll be mounting a lot of problems on the engine.

The more charge the battery drains, the harder it is for the car engine to start. Ultimately, the car will become completely unresponsive.

Is Jumpstarting A Car With A Failing Alternator Dangerous?

No, there’s no associated danger with jumpstarting a car with a faulty alternator.

Once you do the jumpstarting correctly and cables are connected in the proper way, the process is safe. There’s nothing to worry about.

On the contrary, if the proper procedures and steps are not followed, the battery of the donor may drain and eventually die.

It may also affect the alternator of the donor car. In addition, the cable may catch fire or melt in the process.

How Long Can You Drive With A Bad Alternator?

At most, you shouldn’t drive more than 75 to 80 miles with a bad alternator. Let me start by repeating my earlier stance: It’s not engine-safe to drive if your alternator is broken.

But now, you’ve failed to heed the warnings of a failing alternator and it eventually craps out. If that happens, you can drive for 75 – 80 miles.

Depending on the distance and the amount of charge in the battery, you can jumpstart and safely drive home. However, if the battery in the car has drained, you may have to tow your vehicle or buy a new battery.

But make sure you don’t repeat the jumpstart for another trip. Once you get home, drive to a mechanic shop and get a new alternator installed in your car.

Final Thoughts

The next time someone asks you if you can jumpstart a car with a bad alternator, you won’t bulge with a yes. Jumpstarting a car is not a license to abandon your bad alternator.

The more you jumpstart the car, the more damage you’re causing your battery. So, the best bet is to replace the alternator with a new one once it goes bad.

My final advice is that you should always keep the alternator of your car in good condition. This is not a component not to pay closer attention to. It’s one of the live wires of your vehicle.