How long should you wait before turning off the engine after jump-starting a car?
2 Answers
After jump-starting the car, you should keep the engine running for at least 30 minutes to ensure sufficient battery charge. The specific steps for jump-starting a car are as follows: 1. Take one jumper cable and connect one end to the positive terminal of the rescue vehicle's battery, then connect the other end to the positive terminal of the disabled vehicle's battery. 2. Take another jumper cable and connect one end to the negative terminal of the rescue vehicle's battery, then connect the other end to a metal part of the disabled vehicle's engine. 3. Start the rescue vehicle, then start the disabled vehicle following the normal procedure. 4. Once the disabled vehicle is successfully started, let it idle for about half an hour to charge its battery. Note: Always connect the positive terminal first and then the negative terminal when attaching the cables; when removing the cables, always disconnect the negative terminal first and then the positive terminal.
I remember the first time I helped a friend jump-start his car. He thought he could turn off the engine immediately after starting it, but within a few days, the battery died again, forcing him to seek help once more. From then on, I learned that after jump-starting, the engine needs to run for at least twenty to thirty minutes to allow the battery to fully recharge. When a battery is drained from prolonged inactivity, the initial starting current is very high, but the actual charging relies on the alternator working while the engine is running. If you turn off the engine too soon, the battery won’t recover, and the next attempt to start might still be difficult. I usually recommend driving the car around the block or letting it idle, listening for the engine to run smoothly. Only after the battery is fully charged is it safe to turn off the engine, avoiding the hassle of finding another jump-start. After all, vehicles rely on electricity to power various functions like lights and electronic devices, and insufficient charging poses significant risks.
