Skip to Content

How To Hook Up Vehicle Jumper Cables (The Right Way)

How To Hook Up Vehicle Jumper Cables (The Right Way)

Any driver should be prepared for breakdown situations. This means everything from carrying an emergency kit and spare tire in your vehicle to having and knowing how to hook up jumper cables correctly.

Most safety measures use common sense, but booster cables often seem a bit intimidating. Even a seasoned driver might not be sure how to use them safely.

Fortunately, using jumper cables isn’t overly dangerous if you take the time to learn how to use them the right way. And that’s what we’re here for, to talk about how to jump-start your vehicle safely.

Let’s jump in!

What Are Jumper Cables?

Jumper cables are a simple yet effective way to bring your vehicle back to life when the battery doesn’t have enough power to start your car or rig.

Basically, jumper cables are a pair of thick wires with alligator clips on both ends. You attach one end to the dead battery and a grounding spot, and the other clips to a working battery.

When attached correctly, jumper cables allow the working auto or jump starter to provide enough power to start the vehicle with the dead battery.

Are All Jumper Cables The Same?

There are many cables on the market, but they all look relatively similar. It’s essential to know what the differences are between them.

One of the most important factors is the gauge of the wires in the jumper cables. The thicker the wire, the more amperage it can handle or the heavier duty it is. Wire gauge is identified by a number. The lower the number, the thicker the wire. For example, a 2-gauge wire is thicker than a 4-gauge wire.

It’s best to use 1- or 2-gauge rated jumper cables for trucks, SUVs, and RVs, while passenger cars can use 4- to 6-gauge cables.

Another consideration is how long the cables are. Particularly if you are purchasing jumper cables for a larger vehicle, such as a truck or RV, you may want to consider longer leads. A longer cable can be a smart purchase, even for a passenger car. You may not always be able to get two vehicle batteries near enough for shorter cables to reach.

One last consideration is the insulation of the clips. Jumper cables provide for a very real possibility of getting shocked. Purchase jumper cables with the greatest amount of rubber or plastic sheathing on the clamps to help prevent accidental contact.

You could also purchase a pair of mechanics gloves to use when handling jumper cables for a little added safety.

Pro Tip: Need to jump-start your RV? We uncovered Are Car Jumper Cables OK for RVs?

What Is The Correct Way To Hook Up Jumper Cables? 

First, be sure that the batteries in each vehicle are of similar voltage.

Before hooking up jumper cables, position the working vehicle close to the car or rig with the dead battery. Don’t allow the vehicles to touch. Just be close enough for the cables to reach.

With both vehicles turned off and in park, connect one red clamp to the dead battery’s positive (+) post. Then attach the other red clamp to the good battery’s positive (+) post.

Now, connect one black clamp to the good battery’s negative (-) post. Lastly, attach the other black clamp to an unpainted piece of metal on the dead vehicle’s engine block, such as a nut or bolt.

Do not connect the second black clamp to the negative post on the dead battery, as this may cause sparking and ignite battery gasses.

After connecting the jumper cables, start the working vehicle. Let it run at idle for a few minutes to allow the dead battery to receive a charge. Try to start the car or rig with the dead battery. If it doesn’t start, keep the jumper cables connected and let the working vehicle continue to idle while charging the dead battery.

Once you can start the vehicle, remove the jumper cables in the reverse order that you attached them.

If the vehicle with the dead battery still won’t start after a few tries, it’s time to call for additional help.

Which Battery Terminal Do You Connect First When Jumping? 

The first battery terminal to connect when jumping a vehicle is the red clamp to the positive (+) post (or terminal) on the dead battery.

This is because you don’t want any energy going through the cables as you hook them up, which can cause a spark and possibly ignite battery gasses. Hooking up the leads in a different order could also cause a severe shock.

Do You Turn Off The Car Before Removing Jumper Cables? 

Do not turn off the car before removing the jumper cables. The working vehicle supplied enough charge for the car with the dead battery to turn over. However, shutting the vehicle off right away may leave its battery without enough juice to start again. It’s best to drive it immediately for about 30 minutes to allow the battery to regain a deep charge.

Pro Tip: On the hunt for new jumper cables? We found the 5 Best Portable Jump Starters for RVs.

Can Jumper Cables Damage Your Car?

Jumper cables can damage your vehicle … if they are connected improperly. When attached appropriately, being careful not to let the red clamps touch other parts of the auto or the other clamps, jumper cables are unlikely to damage either vehicle.

A common mistake is revving the once-dead vehicle’s engine while the jumper cables are still connected. This could cause some damage to delicate electronics. If you rev the engine, wait until after you have safely disconnected the jumper cables.

Is It Worth Carrying Jumper Cables With You?

As long as you have taken the time to learn how to connect and use jumper cables properly, they can be a lifesaver. There are often helpful folks willing to help you out when your vehicle’s battery is dead but maybe don’t have jumper cables. If you have your own, you’re one step closer to solving the problem without having to call for roadside assistance.

You’ve already taken the step to learn how to safely and properly use jumper cables, so you might as well have them on hand. You might also consider purchasing a mobile jump starter, which allows you to jump-start your vehicle without having another vehicle present. They typically cost between $50 and $200 depending upon how many bells and whistles they come with and how robust they are.

But just having a set of lengthy, heavy-duty jumper cables and the knowledge you’re now armed with should go a long way toward avoiding a prolonged breakdown just because you may have left your lights on.

Have you ever had to use your jumper cables? Tell us about your experience in the comments!

Discover the Best Free Camping Across the USA

To be honest with you, we hate paying for camping. There are so many free campsites in America (with complete privacy).

You should give it a try!

As a matter of fact, these free campsites are yours. Every time you pay federal taxes, you’re contributing to these lands.

Become a FREE CAMPING INSIDER and join the 100,000 campers that love to score the best site! 

We’ll send you the 50 Best Free Campsites in the USA (one per state). Access the list by submitting your email below:

Shaun Hanlon

Saturday 5th of February 2022

Driving the vehicle to charge OT os fine if the vehicle is old. Smart alternators don't charge vehicles when driving. Only at idle. Best to just let it idle.

Robert E Dryden PE

Saturday 5th of February 2022

You can't get shocked on 12 volts, but you can certainly get burned by hot clamps and wires, refer to OHSA about danger of various dc voltage levels. Hooking to frame rather than negative terminal makes no sense. Hooking up hot lead first is common advice but I have seen an engineering explanation. Robert E Dryden PE.

Frank

Thursday 3rd of February 2022

OK, a great topic that baffles many folks..... although your text explanation is great the video tells a different story. Since the actor is attending to the vehicle with a dead battery, all of the video being about how to connect BOTH pos and negative cables to the dead battery is very misleading. Never is it said in the video actually how to do it right. It is way too cute and way to wrong to be anything less than dangerous for those who don't know any better. Stick with the text my friends and cut the video and it will be a great article. Thanks for great content. I read your post every morning.

Dave

Wednesday 2nd of February 2022

You can not receive a "shock" from a 12 or 24 volt system!

Steve McNair

Wednesday 2nd of February 2022

Was hoping you would address (if different) how to connect jumper cables to RV's having several batteries wired in serial (or parallel? Not sure which.)

%d bloggers like this: