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Jump Start Car Battery Right Way

Published Wed July 18, 2018

Has this ever happened to you? You jump into the driver’s seat of your car, in a rush to get your kids to school and yourself to work. You turn the key and get ready to zoom away—but as you turn your ignition, nothing happens. A few clicks or stray sputters of your engine, maybe. But other than that? Nothing.


You probably know good and well what’s happened here. It’s a dead battery, and for some drivers, it means an automatic call to your roadside assistance company.


But actually, if you have the right equipment and a little bit of knowledge, you can fix this problem all by yourself—jumping your engine and getting back on the road in no time flat.

1. How Long Should You Charge a Dead Car Battery?

How long should you charge a car battery?
Few things are more frustrating than getting into your car only to find that the engine won’t start. Often, the problem is as simple as a dead battery. Although this is obviously inconvenient, you can always attempt to jump start the car in order to revive the dead battery. This is assuming you have jumper cables, another vehicle with a working engine and some basic knowledge of how battery recharges work.

If you’ve never jumped a dead battery before, you may have a few questions. For example: How long does it take to charge the battery? How long should you give it before trying to power the engine and get back on the road—and at what point do you throw in the towel and admit that there might be a deeper issue with the car engine?

Jumping a Dead Battery: Birdseye View

To start the process of re-charging the battery,  you’ll first need to get the good car and the bad car as close together as possible. Then, you’ll attach the red/positive cable to the battery terminal in the good car and then to the dead one. You’ll also do the same with the black/negative cable.

Now here is where you’ll want to time things. Turn on the engine in the good car and wait two minutes. Then turn on the bad/dead one and wait an additional two minutes. From there you’ll remove the cable in the reverse order at which you put them on, and you’ll let the car run for two more minutes before you get back on the road.

What if That Doesn’t Work?

So what happens if that doesn’t work? If that’s the case, there may be something else wrong with your vehicle.

Some possibilities for this scenario include:

  • The terminals on your car battery may be corroded and in need of a deep cleaning.
  • Your battery may simply be very old, and beyond the point at which it can be repaired—in which case, of course, it will need to be replaced.
  • There may be a problem elsewhere in the engine—with the alternator, a blown starter, or something else.

Obviously, there are times when a battery recharge is not only possible, but fairly straightforward. So long as you know what you are doing, it shouldn’t take but a few minutes to recharge the dead battery. But if you are still unsure about the process, you may want to request help as it can be dangerous.

If the problem turns out to be something more serious than a dead battery, you’ll want to take your car to your local Meineke Car Care Center, where the problem can be diagnosed and repaired as quickly as possible.


2. How to Charge a Car Battery

How to charge a car battery

Charging a dead car battery is more than simply hooking up a charger if you want to do this job safely. You should know which terminal to remove first if you have to remove the battery, which terminal to hook up first on the charger, how long to charge a dead car battery and more.

Getting Ready to Charge

Before we get into how to charge a car battery at home, you need to know how to prepare to charge the battery. It is very easy to get a good shock if the battery does have some juice. Before you even get started, if you have to remove the battery from the vehicle to charge it, be sure you have the tools for the job. Some batteries are easily accessible; however, some are under or in the fender and some may even be in the trunk or under the seat depending on the make and model of your vehicle.

How to Jump a Car Battery

Be sure all accessories are off and the lights, including the interior light, are off. If you have anything on, it could cause the battery to arc while you are working with it.

Once you get down to the battery, remove the negative or ground cable first. This is always the black cable unless someone replaced the cables with the wrong colors. If you look on the top of the battery, you can see which is which – the ground cable will have a negative (-) sign and the power or positive cable will have a plus (+) sign.

Clean the battery terminals with a terminal cleaning brush and a mixture of baking soda and water to neutralize the battery acid. If the battery terminals and posts have a lot of acid buildup, wear eye protection and a mask so the airborne corrosion does not contact your eyes, nose and mouth. Don’t touch your face until after you’ve washed your hands.

If the battery has removable caps, carefully pry the caps off and check the level of the water. If any of the cells looks low, add distilled water only; and take care to not overfill the battery. Most batteries today are “maintenance-free” so you won’t be able to open them to check the acid level.

Hooking up the Battery Charger

Follow the instructions for your particular charger. Basic instructions for most chargers include:

  • Make sure the charger is off.

  • Hook-up the positive cable on the charger to the positive terminal on the battery.

  • Hook up the negative cable on the charger to the negative terminal on the battery.

  • Set the charger to the slowest charge rate.

  • Turn on the charger and set the timer.

When removing the charger, turn it off first, then remove the positive then negative cable.

How Long Should You Charge a Car Battery?

If the battery voltage is below 11.85 and your charger is putting out a 5-amp charge rate, it will take about 12 hours to fully charge a battery with 400 to 500 cold cranking amps. The same battery will take about 6 hours to fully charge if the charge rate is 10 amps. The lower the open circuit voltage in the battery and the more cold cranking amps, the longer it will take to charge the battery.

If a cell is bad, the battery won’t hold a charge. In this case, bring your battery or your vehicle with your battery to a local Meineke Car Care Center and we will change your vehicle’s battery.

3. Why Won’t My Car Battery Hold a Charge?

Why Won’t My Car Battery Hold a Charge?Knowing how to jumpstart a car battery is a good skill to have—but what happens when it’s not enough? Most of the time when your car won’t start, you assume it’s because there is a problem with the battery. You pull out the jumper cables, jump start it and go on your way. But what if the very same problem occurs the next time you get in the car?

This simply means that your car battery isn’t holding a charge. But why? There are several different causes that could be behind your run-down battery.

The Causes of a Failed Charge

Here’s a quick rundown of some of the most common causes of a battery that won’t hold a charge:

  • You’ve left your lights on, or some other accessory that draws battery power even when your car isn’t running.
  • When you drive the car, the battery isn’t getting recharged, i.e., there is a mechanical charging problem.
  • There is a parasitic electrical drain on the battery, possibly caused by a bad alternator.
  • The battery is simply old and it’s time for you to replace it.

Diagnosing the Problem

While there are multiple causes of a failed charge, you might be wondering how to determine exactly which one is to blame. Perform the following tests to find out:

  • The first thing to do is try to turn on your headlights. If they come on with their normal brightness, your problem is probably a bad starter or poor wiring—not the battery. If the lights do not come on at all, or if they’re dimmer than normal, then the problem is more likely with the battery.
  • To test the voltage of your battery, get a voltmeter and connect the red lead to the positive terminal, the black lead to the negative terminal. Hopefully, you’ll get a reading of over 12.6 volts, showing a fully charged battery—but if not, there’s definitely an issue with the battery being poorly charged.
  • At some point, you’ll want to ask yourself about the condition of the battery itself. Does it look obviously corroded or worn out? Is it more than four years old? If so, then the simplest solution may be to have the battery replaced.
  • Something else to consider is that the problem is your alternator. If you detect cracking or fraying in the alternator cables, that’s an obvious sign that something’s off. And if you jump start the car only for the battery to quickly lose its charge and the engine to stall, that’s suggestive of an alternator issue.

Even if you do believe you’ve discovered the exact problem, you’ll probably want to get an expert opinion. Buying a new battery when the alternator is the real problem—or vice versa—will prove highly frustrating when you end up spending more money than necessary. Bring your car to a local car care center for an inspection so you can get to the bottom of what’s truly causing your lost charge.


4. How to Clean a Car Battery

Why Won’t Your Engine Jumpstart?


If your efforts to jumpstart the battery don’t go anywhere, it’s likely for one of these reasons:


1. First, it may be that the terminals on your car battery need a deep cleaning. We’ll offer some tips for this in just a moment!
2. Your battery may simply be very old, and beyond the point at which it can be repaired—in which case, of course, it will need to be replaced.
3. Finally, note that there could be another mechanical problem somewhere in the vehicle, such as blown fuses or a bad alternator. A Meineke service technician can help diagnose and fix any of these problems.

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