The correct order is: attach the red positive jumper cables to the positive terminals on both batteries first; attach the black negative cables to the donor's negative terminal and to a grounded metal surface on the vehicle with the dead battery; start the donor car, then try to start the dead car; once the dead car runs, remove the clamps in the reverse order: black from the grounded surface, black from the donor battery, red from the donor battery, then red from the dead battery.
Jump-starting a car is a common roadside task, but it carries safety risks. This guide explains the right sequence, safety precautions, and best practices to maximize success while protecting both electrical systems and people nearby.
Preparation and Safety
Before you begin, gather the necessary equipment, inspect the batteries, and prepare the vehicles. This helps prevent sparks, battery damage, and injuries.
These steps ensure you set up the jump safely and minimize the risk of accidental short circuits or battery damage.
- Park both vehicles on a dry, level surface with the engines off. Engage the parking brakes; leave the dead car in Park (automatic) or Neutral (manual).
- Position the cars so the jumper cables can reach each battery without the cars touching.
- Open the hoods and locate the battery terminals. If terminals are corroded, wear gloves and eye protection and clean them gently with a wire brush or cloth.
- Check cables for cuts, exposed wires, or damaged clamps. Do not use damaged cables.
- Attach one red clamp to the positive terminal of the dead battery.
- Attach the other red clamp to the positive terminal of the donor battery.
- Attach one black clamp to the negative terminal of the donor battery.
- Attach the other black clamp to a clean, unpainted metal surface on the engine block or chassis of the car with the dead battery (away from the dead battery itself).
- Double-check that the clamps are secure and that the red and black clamps are not touching each other or any moving parts.
With the cables connected as described, you’re ready to proceed. This setup minimizes sparks near the battery and establishes a proper path for current.
Starting the Cars and Removing the Cables
Once the connections are secure, begin the starting sequence and remove the cables in the proper reverse order to prevent sparks.
The following steps outline how to start the donor vehicle, attempt to start the car with the dead battery, and then safely remove the cables.
- Start the donor car and let it run for several minutes to deliver a charge to the dead battery.
- Attempt to start the car with the dead battery. If it starts, keep both engines running and let the donor car idle for a few more minutes to ensure the dead battery begins recharging.
- If the dead car does not start after a few attempts, stop cranking and reassess connections or battery health; continuing to crank can overheat cables or damage electrical components.
- Remove the cables in this order to minimize sparks: first detach the black clamp from the grounded metal surface on the dead car, then detach the black clamp from the donor battery, then detach the red clamp from the donor battery, and finally detach the red clamp from the dead battery.
After disconnection, let the revived car run for at least 15–30 minutes or drive around to help recharge the battery. Inspect terminals for corrosion and address any buildup to maintain good connections.
What to Do If the Car Won’t Start
If the dead car still won’t start after a successful connection and a few minutes of charging, the battery may be too far gone, or there could be a larger electrical issue. Consider calling roadside assistance or consulting a mechanic to check the battery, alternator, and related wiring. Do not continue cranking for extended periods, and avoid jump-starting if you notice swelling, leaks, or a strong sulfurous odor from the battery.
Tips and Common Pitfalls
Here are quick reminders to improve safety and effectiveness, and to avoid common mistakes during jump-starts.
- Never jump-start a frozen, cracked, or swollen battery. If in doubt, replace the battery instead of attempting a jump-start.
- Avoid smoking, open flames, or sparks near the battery, especially during connections and disconnections.
- Do not allow the clamps to touch each other while connected to the batteries.
- If the engine compartments are very hot or the weather is extreme, pause and recheck connections or seek assistance.
- Consider using a portable jump-start pack as an alternative if another vehicle isn’t available.
Following these tips reduces risk and helps ensure a smoother, safer jump-start experience, even for first-time users.
Summary
Jump-starting a car safely hinges on the order you attach and remove jumper cables: connect positive to positive first, then connect negative to a ground away from the dead battery; start the donor vehicle, then the dead one; and finally remove cables in reverse order. Prepare properly, monitor for safety hazards, and allow the revived battery to recharge before driving long distances. If issues persist, seek professional help to avoid damage to electrical systems or safety hazards.
Do you bump start in 1st or 2nd gear?
2nd gear
You should engage in 2nd gear, since engaging into 1st gear would winf up the engine's RPMs fast enough that it may cause damage. I've also seen people starting by push starting in reverse and engaging in reverse, though 2nd gear pushing forward is still your best bet.
Is there a correct order to attach jumper cables?
One end of the red jump lead should be connected to the flat battery's positive terminal. The lead must not touch any vehicle metal. Attach the red lead's other end to the boosting battery's positive terminal. Take the black lead and connect one end to the boosting battery's negative terminal.
What is the proper jump starting order?
It goes like. This red to the dead. Red to the good black to the good. Then under the hood. Now let's watch as Brian from Henderson Auto puts all of that into action.
Do you put on black or red first?
Two other red clamp to the positive on the good battery. Three black clamp to the negative on the good battery. Four last black clamp to unpainted metal on the dead. Car away from the battery.