12 Tips for Jumpstarting a Vehicle

Whether you’re preparing your spring and summer vehicles, digging out your car from a snowdrift or simply have drained the battery, there may come a time when your car won’t start — and could require a jumpstart. Even if you know the general mechanics behind jumpstarting a vehicle, here are a few additional things to keep in mind.

Finding the battery

Batteries are not in the same place in all vehicles. They may be under the hood, behind the cab, or even in the trunk.

Check the battery voltage

If you suspect a dead battery, check its voltage with a charger. For passenger vehicles, 12.6 volts indicate a full charge when the car is off and no leads are connected; 12.3 volts indicate a half-charged battery. If you get these readings, your issue is not a dead battery.

Make sure the battery is the problem

If you don’t have a charger, you can zero in on a potential battery problem by checking the headlights. If they are dim, your battery is probably the culprit. If they are bright, a jumpstart probably will not help.

Also, putting the key in the ignition to see whether your dashboard lights up as usual is a good indicator. If there is a flicker from your dashboard or you get little sound from your radio, it is probably a dying battery. If there’s no flicker of light or no sound from the radio, it may be an ignition switch problem.

If your engine cranks quickly but does not start, you probably don’t have a dead battery. If it cranks slowly or not at all, then you may have a dead battery.

Consult the owner’s manual

Consult a vehicle’s owner’s manual before doing any maintenance, and especially before jumping a dead battery. Every car is different, so not all jumpstarting procedures will apply across the board. If you can’t locate your owner’s manual, you may be able to find it online.


Wear goggles and/or gloves for protection. Check the battery for leaks, cracks or any other damage. If you find damage, do not jumpstart the car. Call a tow truck or replace the battery instead.

Don’t smoke

It’s common sense to not smoke while jumpstarting, but if you need reminding — you are working very close to a combustion engine. You could spark a fire or explosion if you smoke while jumpstarting a dead battery. Furthermore, batteries emit hydrogen gas as a normal byproduct, and hydrogen gas is highly explosive. Extinguish all smoking materials before jumpstarting your car.

Cable connections

If you don’t have a charger and have determined that the problem is in fact a dead battery, you probably will have taken out the charger cables.

When you connect the cables to batteries of two vehicles — one with a working battery — make sure all connections are firm and that the ground connector isn’t close to any moving parts. Never connect the black cable to the negative (-) terminal on your dead battery! It could result in an explosion. Make sure you connect the black jumper cable to the vehicle body to prevent sparks near the battery.

Don’t let your cars or your cables touch each other

You are dealing with live cables. Touch only the protected handles of the clamps, and don’t let the clamps dangle after you’ve disconnected them. This increases the risk they’ll touch the engine or allow a positive and negative clamp to make contact.

Dealing with loose wires

Don’t try to connect loose wires under any circumstances. Messing with loose wires is dangerous and best left to a professional mechanic.

Allow the battery time to charge

Once you get your car jumpstarted, it is essential to let the car run for a while to allow the battery to charge. If needed, go for a drive — or leave the engine idle in an open garage or in the driveway. If you shut off your car after a short period of time following a jumpstarted battery, chances are the battery will die again. At least 15 minutes of driving or idle time should do the trick.

Lights off/accessories unplugged

To prevent dead batteries in the future, make sure lights are off when you leave the vehicle. In addition, all accessories should be unplugged. Lastly, make sure the trunk and all doors are closed tightly so interior lights shut off.

Professional inspection of electrical system

If a dead battery becomes a recurring problem, take your vehicle to a professional for an inspection of the electrical system. A mechanic should be able to diagnose and fix the problem.

When you need to get going and you’re having trouble getting your car to start, you would do well to keep these things in mind. Don’t panic — you’ll be on your way in no time!

About the author:

Doug Climenhaga is president of SVI International, Inc., a leading supplier of parts for industrial lift equipment, and other repair parts including tire machine parts. With more than 20 years experience in the hydraulic and automotive lift industries, he holds two patents and has designed scores of problem-solving products.


You can be the first one to leave a comment.

Leave a Comment