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How to safely Jump Start a Car

Carrying a set of jumper cables can help you help a fellow motorist—or the other way around. Jump-starting a vehicle is usually pretty simple, but it’s serious business and you have to do it right to do it safely. Every year people are seriously injured while attempting to help another driver with a “jump.” Clip this article and put it in your glove box. Then, before you even connect the cables, go through these steps:


1. Read the manual to check the manufacturer's advice. Some manufacturer's do not allow jump starts. Others require you to remove fuses.
2. Make sure both batteries have the same voltage (most are 12 volts) and same polarity as well (both should have a negative ground). You can check the owner's manual if you can't tell by looking at the battery.
3. Pull the car with the good battery close enough for you to get the cables to reach from one car to the other, but don't let the cars touch. This could short out the battery.
4. In both cars, make sure the the ignition switch is off, as well as the headlights/radio/domelights/etc.. On both cars the parking brake should be set. It's probably not a bad idea to wear safety glasses.
5. Do not smoke or light a match or a lighter near either battery.
6. If the bad battery is frozen, don’t attempt to jump it off at all. It might explode. You can see if it’s frozen if you look through the inspection cap on the top of the battery. The liquid will look frozen.
7. Make sure you are able to tell the difference between the positive and the negative terminals of each battery. The positive one is usually connected to the car’s starting system, and usually has a red cable which has the plus sign (+). The negative one is usually connected to the frame of the car or truck and generally has the minus sign (-).

To hook up your cables--
1. Clamp the positive cable to the positive terminal of the weaker/bad battery. Make sure the other end doesn’t touch any part of the car’s engine or body or it could cause a dangerous spark.

2. Clamp the other end of the positive cable to the positive terminal of the good battery.

3. Clamp the negative cable to the negative terminal of the good battery.

4. Clamp your other end of the negative cable to a clean metal part of your engine (like a bolt head or bracket) in the car with the weaker/bad battery. Keep the clamp away from the battery, any moving parts, and away from the fuel system.

CAUTION: Don’t attach the negative cable to the negative terminal of the weak battery! This could ignite hydrogen gas directly over the battery. A battery explosion can cause serious injury. Even if you’ve gotten away with it before, you should use a metallic engine part instead.

Now start the car with the good battery, let it charge the weaker/bad battery for 1-2 minutes, then try to start the car with the weak battery. If it won’t start, shut off both ignitions, make sure the cable clamps are making good contact and then try it again.When the car with the weaker/bad battery starts, wait (about 15 seconds or so) to make sure it doesn’t stall.

Disconnect the cables in the reverse order: First remove the negative cable from the car you jumped, then the negative cable from the car with the good battery. Then remove the positive cable from the car with the good battery (don’t touch a grounded part of either car with the clamp of the positive cable). Finally, remove the positive cable from the car with the weaker/bad battery. Remember, both engines will be running, so be careful as you remove cables to avoid belts, fans and other moving parts.

TIP: If you live in a very cold climate, buy the thickest-gauge cables you can find (the lower the number, the thicker the cable).  You can check out all our articles on cars at http://www.wholesalecarsdirect.com
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