The timeline
- Hooking up: a few minutes, once the hood is open and the jump points are reachable. Some cars hide the battery in the trunk or under a seat and have remote jump points under the hood.
- A battery that's just weak: often starts within a minute or two of connecting.
- A battery that's completely flat: may need several minutes connected before it will crank, and sometimes more than one try.
- Total time on scene: for most jump starts, a short stop.
Why a dead battery can take longer
A jump doesn't recharge your battery. It lends enough power to crank the engine. A battery that's fully drained, or very cold, has almost nothing to contribute, so the jump has to do more of the work. Cranking for a long time in one go can overheat the starter, which is why the right approach is short tries with a pause in between.
How long to drive after a jump
Drive for at least 20 to 30 minutes, ideally at steady speed on the highway, so the alternator can recharge the battery. Short trips with lots of stops, and running the heater, seat heaters and defroster on a cold day, slow the recharge. If you shut the car off right away, it may not start again.
If it won't stay running
If the car starts and then dies within minutes, the alternator is the likely problem, not the battery. If it starts fine today and is dead again tomorrow, the battery may not hold a charge, or something is draining it while the car is off. Either way, it needs a test. Read battery, alternator or starter for the signs.
When not to jump
Don't jump a battery that's cracked, swollen, leaking or frozen, or that smells like rotten eggs. Don't keep trying if the engine cranks normally but won't fire; that isn't a battery problem.
Our jump start service
PS Towing & Recovery jump-starts cars, pickups, vans, hybrids and EV 12-volt systems, 24/7, for $65 plus $3 a mile for the drive to you. If the jump doesn't hold, we can tow the car on the same call. See jump start service or call (414) 254-1468.