Whether youíre 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 wonít start ó 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 donít 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 thereís 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 donít have a dead battery. If it cranks slowly or not at all, then you may have a dead battery.
Consult the ownerís manual
Consult a vehicleís ownerís 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 canít locate your ownerís 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.
Donít smoke
Itís common sense to not smoke while jumpstarting, but if you need reminding ó 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 donít 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 ó one with a working battery ó make sure all connections are firm and that the ground connector isnít 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.
Donít let your cars or your cables touch each other
You are dealing with live cables. Touch only the protected handles of the clamps, and donít let the clamps dangle after youíve disconnected them. This increases the risk theyíll touch the engine or allow a positive and negative clamp to make contact.
Dealing with loose wires
Donít 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 ó 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 youíre having trouble getting your car to start, you would do well to keep these things in mind. Donít panic ó youíll 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.

Source: http://www.carversation.com/2014/01/...ing-a-vehicle/