If your car won’t start, you may want to jump-start it so you can drive it to a mechanic or recharge the battery. But before you attempt to jump-start a car, you need to determine if the battery is really the problem. If the headlights or other lights still work, the battery isn’t dead, and jump-starting won’t help. Jump-starting the vehicle is also not the answer if the motor cranks, although the battery may be partially drained if the engine turns over sluggishly a few times.
Before you connect the jumper cables, get ready by following these steps:
Car batteries contain acid, so you can get an acid burn if you touch the liquid inside the battery. It will also eat holes in clothing. Wear safety goggles and gloves.
Connecting the Jumper Cables
Your vehicle’s owner’s manual should have information on jump-starting (or tell you not to jump-start it). If you can’t find the battery easily, the manual will tell you where to attach the jumper cable clamps.
Don’t allow the clamps to touch each other while you are connecting them to or disconnecting them from the batteries.
Batteries create hydrogen, which can build up and, if ignited, explode. (Do not smoke while jump-starting a vehicle.) When an electrical circuit is being closed, there is a possibility of creating a spark. This procedure for connecting jumper cables minimizes sparks near the batteries:
- Connect one red clamp to the positive (+) post of the dead battery.
- Connect the other red clamp to the positive post of the good battery.
- Connect one black clamp to the negative (-) post of the good battery.
- Connect the other black clamp to bare, clean metal away from the battery of the dead car. Brackets or bolts on the engine are usually good places to connect the clamp, but check the owner’s manual for suggestions.
Most jumper cables have red and black clamps, but if your set uses different colors, that’s OK. If you have cables with yellow and black clamps, for example, replace the word “red” in the above instructions with “yellow.”
Before starting either vehicle, be sure the jumper cables won’t be damaged by moving parts (fans, belts or pulleys) when the cars are running. Close vehicle doors so dome lights don’t draw power.
Run the engine of the vehicle that starts for about three minutes. Then try starting the vehicle with the dead battery. After it starts, disconnect cables in reverse order from when you connected them and drive the car for about 30 minutes to charge the battery — if you turn it off before the battery charges, you’ll have to jump-start it again. The other option is to drive it to a mechanic who can check it over or charge the battery for you.
If the vehicle doesn’t start after a few tries, give up; you may have a different problem. Disconnect the cables in reverse order.