Dead or weak battery? Jump-starting a vehicle is easy and safe if you follow these four simple steps. It takes only a few minutes.
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:
Connect to the positive cable to the positive terminal of the weak battery. Connect the negative terminal to metal on the engine.
Connect to the positive cable to the positive terminal and the negative cable to the negative terminal of the good battery.
Caution: Don't attach the negative cable to the negative terminal of the weak battery! This common mistake could ignite hydrogen gas directly over the battery. Battery explosions can cause serious injury. Even if you've gotten away with it before, use a metallic engine part instead.
Now start the car with the good battery, let it charge the weak battery for 5 minutes, then try to start the car with the weak battery. If it doesn'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 weak 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 weak battery. Remember, both engines will be running (with any luck!), so work carefully 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).