You walk out of the local lumber yard and notice a car with its hood up and a befuddled person peeking around underneath, looking at the engine in despair. You head over to lend a helping hand and find out what’s wrong and find out that a turn of the key in the ignition doesn’t seem to be doing anything. The car battery is dead and they have places to be.

Before you resort to calling AAA, lets help you not look like a putz when asked to jump start a car and help prevent you from shocking yourself, blowing something up or shooting metal allover the place in the process.

How to Tell if a Car Battery Is Dead

How to tell when a car battery is dead
How to tell when a car battery is dead

Before you jump into jump starting a car, you need to determine that the battery is the reason the car isn’t starting. This is easier than you may think. If you turn the ignition and the engine cranks, a dead battery isn’t the problem and a jump start won’t do a bit of good. If you turn the key and absolutely nothing happens there’s a good chance it’s a dead battery. If you turn the key and you get a weak electrical response (ie. dim lighting, radio cuts in and out, etc…) that’s also a sign that the battery doesn’t have enough juice to power the starter and crank the engine.

How to Jump Start a Car with Cables

Obviously, you should always carry jumper cables in your car with you. You never know when you’re going to need them. They’re cheap so there is really no excuse.

1) Find both vehicle’s batteries

Hint, they aren’t always under the hood. Sometimes they’re in trunk of the car or elsewhere, sometimes they are under several layers of plastic shrouding. If you find yourself searching and at a loss, check the owner’s manual.

2) Bring the live car and park it close to the dead car

Jumper cables are only so long after all. Don’t allow the cars to touch, and never connect cables to a car that’s running.

3) Make sure both cars are turned off, as in the ignition is in the off position

Make sure everything is shut off in both cars, including headlights, radio, A/C, etc.

4) Check the batteries

Do a quick visual inspection of each car’s battery. Look for leaks or cracks or for any damage. If the battery is damaged, stop and call a tow truck.

5) Locate the battery terminals

The positive terminal is, typically, indicated by a positive (+) sign and the color red. Negative is indicated by a negative sign (-) and the color black.

6) Corrosion control

If there’s any corrosion or buildup around the terminals, disconnect the cables from the terminals and remove the corrosion with a wire brush or a cloth. Sometimes corrosion is the real problem rather than the battery’s power.

7) Don’t cross cables

When you start connecting cable clamps to the battery it is imperative that you do not allow the cable clamps to touch on another. This can cause arcing current which can injure you and damage the cars. I learned this lesson the hard way as a kid when I dropped a socket wrench on a spare car battery sitting in my parents garage, that wrench instantly turned into a molten metal shooting rod of death destroying both the wrench and the battery and nearly burnt the crap out of my legs.

People actually weld with car batteries McGyver style, though I wouldn’t recommend it:

8) Connect the jumper cable clamps

Source: [ eHow.com, Quamut.com ]
Source: [ eHow.com, Quamut.com ]
Connect the red clamp to the positive (+)/red terminal of the dead battery. Connect the other red clamp to the positive (+)/red terminal of the good battery. Connect the black clamp to the negative (-)/black terminal of the good battery. Connect the other black clamp to a piece of grounded, non-painted metal that’s connected to the engine on the dead car. Typically, you’ll see a small spark when you make the connection if you’re making a good grounded connection.

You should never attach the black clamp to the negative terminal of the dead battery. A dead battery produces hydrogen gas. If the final negative connection is made on the negative battery post and a spark is created the battery can explode. And when I say explode, I mean explode. As in the whole top of the battery blowing off – shooting plastic shrapnel all over the place and battery acid sprayed all over you, including your face and eyes.

In the United States in 1994, a research note by the National Highway Traffic Safety Association estimated that about 442 persons were injured by exploding batteries while attempting a jump-start.

9) Start the live car

Start the engine in the car with the good battery. Allow it to idle for at least five minutes so you can trickle charge the dead battery a bit. Do not rev the engine, however, you can hold down the throttle just above idle speed for around 30 seconds to a minute.

10) Try starting the car with the dead battery

If the car won’t start give it another minute or two. If the dead car starts, remove the jumper cables in the reverse order you connected them. Drive for at least fifteen minutes so you can allow the alternator to charge the battery before turning the car off again.

11) If the car still won’t start

Check all your connections, then reconnect and try again based. If you’ve tried twice and still can’t get it going it’s probably time to call in some backup. Your battery may no longer hold a charge. You can get your battery tested at a shop or auto parts store for free to determine what the issue is.

How to Jump Start a Car Without Cables

sti-stick-shift-manual-car
STi Stick Shift

If you drive a standard transmission vehicle, you can jumpstart the car without any cables at all:

  1. Find a stretch of clear downhill road or several very strong dudes to push.
  2. Depress the clutch and put the car in first gear, keep the clutch pressed in.
  3. Turn the ignition to on.
  4. Take your foot off the brake and get the car some speed, keep the clutch fully depressed.
  5. Get up to around 5 or 7 miles per hour.
  6. Drop that clutch, like a 16 year old on his first solo drive in his dad’s vette. You should feel the engine turn and start. If it doesn’t start the first time, depress the clutch and release it again.

Jump Start Any Car On Your Own

If you live, work or travel to secluded places you really should buy a portable jump starter. It’s basically a rechargeable battery in a plastic shroud with one set of jumper cables. It replicates a live car, which you might not have access to, and allows you to jump your car without assistance. A real life saver if you find yourself stranded in white-out conditions, at a secluded fourteener trailhead, without cell service at 8pm after a long day of climbing. Or more simply, if you find yourself in a parking lot full of A**holes too busy to lend a helping hand.