You know the scene. You walk to your car, open the door, climb in, and insert your keys into the ignition. Click, click, click, click. Nothing. You whisper a prayer, "Please, God, make it start this time." Click, click, click, click. Nothing. You glance at the fuel gage. Half a tank left. You glance at the headlights. Grrrrr! You left them on. Your battery is dead. You need a boost, a.k.a. a jump-start, to get you moving.
Fortunately for you, this is not a major car repair. But it is a repair of sorts that should never be taken lightly. The smart driver will know that this day is bound to come at some time or another and will be already prepared with a set of high quality booster cables that are at least fifteen feet long, so they will easily be able to reach from the boosting car’s battery to the dead battery.
Before starting the boosting procedure, turn off all accessories on both vehicles such as the headlights, radio, air conditioner, windshield wipers, et cetera. This will help prevent any power surges that could affect these items, but more importantly, it will keep these accessories from consuming more available power than the alternator is producing while the engine is idling. You should leave the boosting vehicle at an idle.
When you look under the hood of each car, you will locate the battery by looking for a plastic bright red cap or post labeled with a "+" sign. Close by, you will also see a black post or cap labeled with a "-" sign. Lift up any post-covering caps, and inspect all battery posts to make sure they do not have loose, dirty, or corroded connections. If they are loose, tighten them the best that you can and then get them completely tightened as soon as you are able to prevent future discharging of the battery. If they are dirty, you can wipe them with a rag. If there is corrosion, then you can pour an acidic drink such as soda water or a carbonated beverage over the post.
Now it is time to start connecting the cables to the posts. In order to ensure maximum safety, you should be careful to always put the cables on and take them off in a very specific order. IMPORTANT! Once you start making the connections, never let the ends of the cables touch each other or any other unintended metal. Many batteries have full plastic handles used for lifting them. You can opt to carefully attach the cable ends to the plastic handle to prevent accidentally touching any unintended metal.
Attach the red, positive + cable to the post of the DEAD BATTERY! A good way to remember which goes first is by remembering this rhyme: Red to dead.
Attach the other end’s red, positive + cable to the post of the BOOSTING BATTERY.
Attach the black, negative " - " cable to the post of the BOOSTING BATTERY. If the boosting vehicle’s battery does not have an exposed negative " - " battery post, then connect the cable clamp to an unpainted piece of metal eighteen inches away from the battery. (The engine block is usually a safe alternative.)
Be very careful not to allow the cable or the clamp to come in close contact with any moving parts such as the radiator fan or any of the belts.
Attach the black, negative " - " cable to an unpainted piece of metal eighteen inches away from the DEAD BATTERY. (Again, the engine block is usually a safe alternative.) If all cables are properly connected, this final negative cable should produce a slight spark. If it doesn’t, go back and check the connections of each clamp.
It is important to ensure that neither the cable nor the clamp come in close contact with any moving parts such as the radiator fan or any of the belts.
Rev the engine of the boosting battery to 2000 RPM and hold it for two minutes. (This step may not be necessary, but it is helpful for speeding up the charging of an especially discharged battery.)
Attempt to crank the engine of the vehicle with the dead battery. If it does not start, wait an additional two to four minutes before trying again.
Once the car is started, remove the cables in the reverse order of how you put them on. First, you will remove the black, negative clamp from the previously dead vehicle. Second, you will remove the black, negative clamp from the boosting vehicle. Third, you will remove the red, positive clamp from the boosting vehicle. Fourth, you will remove the red, positive clamp from the previously dead vehicle.
Run the newly boosted vehicle for a minimum of fifteen minutes to adequately recharge the battery before turning it off.
Now that you are an expert vehicle booster, keep your eyes out for other stranded motorists. They will be so grateful!