What is the correct procedure for jump-starting a car?
3 Answers
The correct procedure for jump-starting a car is: Park both vehicles facing each other and prepare two jumper cables. Open the hoods and connect the positive and negative terminals of both car batteries using the jumper cables—red to positive and black to negative. Start the rescue vehicle and let its engine idle. Attempt to start the stalled vehicle. If the battery is dead, the car should start quickly, and the alternator will begin charging the battery. Precautions for jump-starting: Before connecting the cables, ensure the engine is turned off. Follow the connection steps strictly: connect the positive terminal first, then the negative, and ensure the positive and negative terminals of both cars do not touch. The disconnection sequence is the reverse of the connection sequence—remove the negative cable first, then the positive. When purchasing jumper cables, choose genuine, quality-assured products. Opt for cables with an outer diameter of at least 10mm and a length of around 3 meters.
As a veteran driver with over a decade of experience, I've jump-started cars multiple times and know that the key lies in a safe and orderly process. First, park the two vehicles close to each other, turn off both engines, and engage the handbrake to prevent any movement. When using jumper cables, connect the red clamp to the positive terminal (marked with a +) of the donor car's battery, then attach the other end to the positive terminal of the dead battery. Connect the black clamp to the negative terminal (-) of the donor battery, but do NOT attach the other end directly to the negative terminal of the dead battery—instead, find an unpainted metal surface like an engine hook or chassis to avoid sparks that could cause battery explosion. Then start the donor car and let it run for about five minutes to charge the dead battery; afterward, attempt to start the stalled vehicle. Once it starts, don't drive off immediately—rev the engine for about ten minutes to continue charging. Remove the cables in reverse order: first disconnect the black clamp from the stalled car, then from the donor car; follow the same sequence for the red clamps. After jump-starting, it's advisable to visit a repair shop immediately to check if the battery is aging, preventing repeated failures. Regularly inspecting the cables for wear is also crucial—replace damaged ones promptly to ensure reliable emergency performance.
I often repair my own car, and jump-starting seems simple but requires skill. In terms of tools, choose high-quality jumper cables and don’t skimp on cost. Park both cars head-to-head and turn off all engines. Connect the cables: attach the red clamp to the positive terminal (+) of the helper car’s battery, then clamp the other red end to the positive terminal of the dead battery. Attach the black clamp to the negative terminal (-) of the helper car’s battery, and the other end to a bare metal part of the engine block of the dead car—avoid connecting to the battery to prevent hazardous gas release. Start the helper car and wait for ten minutes to stabilize the power before attempting to start the dead car. After a successful start, let the car run for at least twenty minutes to recharge the battery. Remove the cables carefully: first detach the black clamp from the dead car, then from the helper car; follow the same order for the red clamps. If you smell sulfur or see smoke during the process, stop immediately for safety. Jump-starting is an emergency measure—afterwards, test the battery voltage to confirm if a replacement is needed.
