|Before you begin.
Only attempt to jump cars or trucks that are similar to your
own vehicle. Commercial trucks can have positive ground, while
motorcycles, snowmobiles, and tractors can have 6-volt systems. Jumping
either of these from a standard car can cause an explosion, fire,
electrical system damage, and serious personal injury. Leave the job
to a pro in this case.
Never let the red and black clips touch each other. Bad things will
happen. Never look directly at either of the batteries, and wear
glasses or a face shield if possible. Batteries build up gases that
can explode. If the dead car doesn’t start easily, give up and call
for help. Some people flood their cars in cold weather. This can
lead to a build up of raw gasoline in the crankcase. It is possible
that this gas will explode and damage the engine. Even if it does
not explode, the gas will thin out the oil, leading to engine damage
from rapid excessive wear. If the dead car is badly flooded, consider
changing the oil as soon as possible.
|Move the cars close enough so the jumper cables will reach.
If you cannot do this safely, call a tow truck or 911 for help. Never
block a lane of traffic to jump a car, or drive the wrong way down a
street or freeway to reach a stranded car.
|Make sure that the source vehicle is running, the dead car is turned off.
|Connect cables to the dead car.
Connect the black clip on the dead car to the battery negative (-) post.
Connect the red clip on the dead car to the battery positive (+) post.
|Connect cables to the running car.
First, connect the red clip on the running car to the battery positive (+) post.
Then connect the black clip to something metal on the running car. Do not
connect this final connection to the battery. There will be a spark when
you make this connection, and you do not want that spark near a battery
that is possibly venting explosive gases.
|Let the running car charge the dead car for about 30 seconds.
|Start the dead car.
You may have to give the running car a little gas to compensate for
the additional electrical system load from the dead car. That is
normal, but don’t floor the gas pedal.
|Disconnect the source car.
First remove the black clip from the source vehicle.
Then remove the red clip from the source vehicle.
|Disconnect the formerly dead car.
First remove the red clip from the formerly dead vehicle.
Then remove the black clip from the formerly dead vehicle.
|Let the formerly dead car recharge.
Run the formerly dead vehicle for about 45 minutes to recharge
the battery. Make sure that the battery light does not come on,
and that the battery charge meter (if you have one) shows a positive
charge current. If you get a battery light or see a zero or negative
charge rate, take the car to a repair shop right away since it likely
will not restart on its own.
|Have the battery checked.
If you do not know why your battery was dead, take the car
to a battery shop to have the battery checked out. It is possible
that the battery is bad. Older batteries are prone to developing
a shorted cell, which renders them unable to start a modern car.