Manual / Winter emergencies
How to Jump-Start a Car Safely, Step by Step
The correct cable order, where the last clamp goes and what not to do on a cold morning.
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A jump-start is simple, but the order matters. Doing it wrong can damage electronics or, rarely, ignite hydrogen gas around the battery.
Before you start
Both cars off, in park, parking brakes on, not touching each other. Glasses and gloves on. If the dead battery is cracked, leaking or frozen (bulging sides), do not jump it.
The order
- Red clamp to the dead battery's + post.
- Other red clamp to the good battery's + post.
- Black clamp to the good battery's − post.
- Last black clamp to bare, unpainted metal on the dead car's engine block, away from the battery.
- Start the good car and let it run 2–3 minutes, then try the dead car.
- Remove clamps in reverse order. Drive at least 20 minutes.
Needing jumps more than once a winter is a sign the battery is losing capacity. Before buying new, some people try a reconditioning method. We reviewed the Easy Battery Fix guide to see what it really offers.
Read our review →Portable jump starters
A compact lithium jump pack lets you start a car without a second vehicle. Keep it charged; cold drains it too.
If you keep finding yourself reaching for cables, this battery revival guide may be worth a read before you replace anything.
| Easy Battery Fix | Step-by-step guide for testing and bringing back tired batteries | See it |
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