What is the correct order to connect jumper cables?

Red to the dead battery's positive (+), red to the donor battery's positive (+), black to the donor battery's negative (−), and finally black to unpainted metal on the dead car — not to the dead battery. Disconnect in the exact reverse order.

Why not connect black to the dead battery's negative terminal?

The final connection completes the circuit and often makes a small spark. Batteries can vent hydrogen gas, so the spark must happen away from the battery. Grounding to bare engine or chassis metal achieves that. It also protects the dead car's electronics from a surge.

How long should I drive after a jump start?

At least 15–30 minutes of actual driving (not idling) to give the alternator time to recharge the battery. Even that may not fully charge a deeply drained battery — a plug-in charger overnight is better if the battery was completely flat.

Can I jump start a car with a portable jump starter?

Yes — and it is simpler: red clamp to the dead battery's positive (+), black clamp to unpainted metal or the negative terminal per the unit's instructions, start the car, then disconnect. Keep the jump starter charged; they lose charge sitting in a trunk over months.

Back to battery

How to Jump Start a Car

About 15 minutesEasy11 steps

A dead battery strands more drivers than any other fault, but a jump start takes ten minutes with a set of cables and a second vehicle — or a portable jump starter. The cable order matters: connecting in the wrong order can spark near the battery or damage electronics. Follow the steps in order.

Car batteries can release hydrogen gas, and a spark at the wrong moment can cause burns. Never jump a battery that is cracked, leaking, swollen, or frozen. If the battery shows any of those signs, replace it instead. Keep cable clamps from touching each other once connected to a battery.