Is Jumpstarting A Car Bad For Your Battery?

A dead battery can cause you frustration, and jumpstarting is an easy way to start and keep your battery running to your destination.

However, there have been issues concerning damaged batteries as a result of the jumpstart.

The primary question addressed by this article is whether jumpstarting your car is bad for your battery.

This piece further explains the safest way to jumpstart your car and other safety tips. 

Can jumpstart damage your car battery?

The answer is both yes and no, and this is the reason why. It is improbable that a jumpstart may cause damage to your car battery on either side.

The reason is that 12-volt batteries have no power to cause major damage to the cars’ electronic components. Furthermore, you may find the integrated anti-surge protection as you charge. 

On the flip side, jumpstarting can damage the car battery due to improper connection of the jumper cables to the donor’s and recipient’s car.

Therefore, there should be no damage to your vehicle battery unless you touch the leads to another piece, which may lead to shorting one or more of the vehicles’ delicate components. 

In addition, cranking the car with a bad battery has a significant impact on the jumpstarting process.

The safe way is by charging the dead battery with a good battery till the dead battery has adequate power to start. After that, disconnect the cables and crank the vehicle with the dead battery. 

The dangerous way is cranking the car with the dead battery as the vehicle with the good battery continues to run, with both batteries wired to each other.

This technique will cause a heavy load on the battery that needs a high current. Removal of this load from the good battery can cause a load dump.

This is when there is a drastic fall in current and a sudden increase in voltage caused by the inductance of the winding field in the alternator.

This occurrence may cause electrical issues though not necessarily. The safe method is preferable to avoid taking chances that may end up in negative consequences.

How do you connect the cables in the correct order to avoid battery damage?

First, connect the positive cable to the positive terminal on both vehicles. After that, on the charged vehicle, connect the negative cable to the negative terminal.

The other negative cable connects it to an unpainted metal frame part of the dead car but is distant from the dead battery. 

Why attach the positive cables first?

When attaching cables to jumpstart your car, you should start by connecting the positive ends of the cables first, instead of connecting both the positive and negative terminal on the car with a working battery.

The reason for this is to prevent a short when trying to revive the dead battery. If you connect both terminals on the good car battery, the other ends of the cables come into contact as you open the dead car’s hood.

This will result in a short that can damage the functioning car’s computer systems. 

Why should you connect the end of the last cable to the frame instead of the battery?

Connecting the last negative cable to the metal frame of the dead car prevents any possible damage to the dead battery.

Most times, you can’t always be certain of the reason behind the dead battery. It may be an issue with overcharging, or there could also be vapors leaking from the dead battery without your notice.

Connecting the last negative cable without proper knowledge of what caused the dead battery may cause sparks.

That is why you connect the cable as far as possible from the battery to prevent probable explosion caused by the ignition of the sparks with the leaking vapors from the bad battery. 

Effects of crossed wires

Modern vehicles depend on several computers to power vital functions and entertainment. Crossing wires can result in potential damage to your battery, and here is why.

Connecting a positive cable to a negative terminal and vice versa can cause an electric short that could burn one or several of the multiple computers that power your car.

The worst part is that it may go unnoticed till you use your power windows or switch on your radio, and they do not respond. 

When my jumper cables are sparking

Sparking during a jumpstart is always risky because there is a probability of the battery exploding and splashing acid on your face.

It would help if you connected the negative jumper cable to the car body and not to the battery’s negative terminal to prevent sparking. Moreover, always ensure the jumper cables are accurately connected. 

Safety tips when jumpstarting your car

  • Do not jumpstart your car when smoking to avoid causing an unnecessary fire. 
  • Always put the vehicle in park mode. 
  • Avoid the cables dangling from the car. 
  • Do not use low-quality cables, instead opt for high-quality ones.
  • Check your car manual for directions. 
  • Always have a wire brush if there is a need to clean the battery terminals to enable the proper cable to terminal connection. 

The electrician advice

To get the best results with minimal risks, you should be willing to invest in a good set. The problem with getting a cheap, low-quality set is that it has regular fails, and you will end up paying more due to constant replacement.

These fails may have damaging effects, especially on your car battery. Some of the common problems associated with a low-quality set include; 

  • Damaged battery
  • Damage to either of the car’s electrical components
  • Corrosion
  • More than one cranking try
  • Pricier
  • Poor contact with the terminals
  • Low current conduction

A good high-quality set is worth the investment

Can jumpstarting fail to work?

Jumpstarting may not always be a solution, especially on a completely dead battery. In normal instances, charging a completely dead battery for several minutes before starting it works.

Nevertheless, if it does not work, check the battery’s terminals for corrosion, or the battery itself may be too old and beyond repair.

However, do not limit your options to these two problems only as the issue may be a blown starter, an alternator, or any other component elsewhere.


It is essential to take all necessary precautions when jumpstarting your car so that you can prevent potential damage to your car battery and the donor’s car battery.


Leave a Comment