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  • zaken1 01/28/09 10:12 pm PST

    It was very wise of you to ask; instead of guessing. A vehicle's electrical system can be seriously damaged by improperly connecting jumper cables.
     
    Car batteries are marked with a "+" (positive) and a "-" (negative) symbol next to the terminals. It is very important that you find these markings on the battery in each car. One cable goes from the plus terminal on one battery, to the plus terminal on the other battery. The other cable goes from the minus terminal on one battery, to the minus terminal on the other battery. So you always connect between two terminals that have the same symbol.
     
    It is customary to use the jumper cable with the black clamps on the negative terminals, and the jumper cable with the red clamps on the positive terminals. But this is not essential; the essential thing is to NEVER permit the cables to touch each other nor to touch any other metal part of a car, and to NEVER connect a minus terminal to a plus terminal.
     
    The jumper cable clamps must be securely fastened to the metal part of the battery cable end. If there is a plastic or rubber cover over the cable end, it must be moved out of the way before attaching a jumper cable.
     
    BE EXTRA CAREFUL TO NEVER LET THE TWO JUMPER CABLE CLAMPS TOUCH EACH OTHER WHEN THEY ARE CONNECTED TO A BATTERY. THE POSITIVE CABLE SHOULD ALSO NOT BE ALLOWED TO TOUCH ANY METAL OBJECT OTHER THAN THE TWO PLUS BATTERY TERMINALS.
     
    Both ends of the positive cable should be connected first. After that, connect both ends of the negative cable. Some instructions recommend connecting the negative cable to a clean bolt on the engine of your car; instead of to the negative battery terminal. It is safer to do it that way, because there is less chance of a spark igniting the hydrogen vapor; which is always around batteries to a small extent (especially in a weak or discharged battery). But the other end of the negative cable can either go to the negative battery terminal in the boosting car, or to a clean engine bolt in the boosting car. (because there is less chance of there being hydrogen vapor near the battery in the boosting car)
     
    Attach the cables while neither engine is running. If the battery in your car is very weak, it is better to attach the cables, and then run the engine in the boosting car at a speed equivalent to what it sounds like at about 30 mph, for about 5 minutes. This will pre charge the battery in your car; which will make it easier to start. Then try starting your car (while the engine in the boosting car is still running). Once your engine starts, let it run for a few minutes before disconnecting the jumper cables; as this will make it less likely to stall. You can then shut off the engine in the boosting car, and remove the cables. Do not shut the engine off in your car until it has run for at least a half hour. It is better to drive it, rather than let it idle, during that time. And it is better to do this process during daylight; when the headlights will not be running and draining the battery.
     
    It is best to turn off the lights and all electrical accessories in both cars while jump starting. But sometimes you may need to keep the lights on in the boosting car for safety, or in order to see.
     
    If your car will not restart after running for about a half hour; the battery cable connections may need to be thoroughly cleaned; or both the battery and the alternator in your car will probably need to be tested, and at least one of those items replaced.

  • lokki 01/29/09 6:24 pm PST



    Although the battery is in the trunk, Look under the hood for a terminal box with a red plus sign on it. Inside, you'll see a nice big terminal for the positve connection. You can ground the negative terminal to the body

    Be sure to follow all the advice in the post above, so you don't end up with an expensive repair.

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