How to Jump Start a Car
A dead battery is one of the most common roadside problems. With a second vehicle and jumper cables, you can restart safely — as long as you connect the clamps in the right order.
Cable Order
- Red (+) to the dead battery's positive terminal
- Red (+) to the good battery's positive terminal
- Black (−) to the good battery's negative terminal
- Black (−) to an unpainted metal ground on the dead car, away from the battery
Start and Remove
Start the booster car, let it run a few minutes, then start the dead car. Once running, remove cables in the reverse order. Keep the revived car running for at least 20 minutes to recharge.
Safety Warnings
Never let the clamps touch each other, and never connect black to the dead battery's negative post on some vehicles (sparks near battery gas can ignite). If the battery is cracked or leaking, call for help instead.
Safety First
Never let the cables touch each other mid-connection, and keep sparks away from the battery. A 12-volt battery can vent gas that ignites, so connect in the right order and keep faces back when making the final clamp.
The Correct Order
- Red to dead positive, red to good positive
- Black to good negative, black to dead ground (metal)
- Start the good car, then the dead one
After It Starts
Remove cables in reverse order, then drive at least 20 minutes so the alternator recharges. If it dies again, the battery or alternator has failed and needs service — a jump is a temporary fix, not a cure.
Hybrid and EV Cautions
Hybrids have a 12-volt battery for starting and a high-voltage pack for drive. Only jump the 12-volt terminal; never touch the orange high-voltage cables. When unsure, call a pro rather than risk a serious shock.
If It Will Not Start
If the jump yields only clicks, the battery may be too far gone or a cable is loose. Recheck clamps and try a second car. Persistent failure points to the starter or alternator, not just a weak battery.
DriveReady Hub — Informational only. Not affiliated with any DMV or government agency.