Five Steps to Jump‑Start a Car, Safely and Correctly

The five steps are: prepare the cars and turn everything off; connect the red clamp to the dead battery’s positive terminal, then the other red clamp to the good battery’s positive; connect the black clamp to the good battery’s negative terminal, then the other black clamp to an unpainted metal ground on the disabled car; start the donor car and then the disabled car; disconnect the cables in reverse order and let the engine run. Below, we explain each step, essential safety checks, and what to do if the car still won’t start.

The 5-step procedure

Follow this sequence exactly to minimize sparks and protect vehicle electronics. These instructions apply to most 12‑volt, negative‑ground vehicles using traditional jumper cables and a healthy donor car (or a jump starter that mimics one). Always consult your owner’s manual for model-specific guidance or designated jump posts.

1. Prepare and position the vehicles. Park nose-to-nose or side-by-side so cables reach without stretching. Put both vehicles in Park (automatic) or Neutral (manual), set parking brakes, turn off engines and accessories, and ensure both systems are 12‑volt negative‑ground.
2. Connect positive to positive. Attach the red clamp to the disabled car’s positive (+) terminal or marked positive post. Attach the other red clamp to the donor car’s positive (+) terminal or designated positive jump post.
3. Connect the negative safely. Attach the black clamp to the donor car’s negative (−) terminal or designated negative post. Attach the remaining black clamp to a solid, unpainted metal point on the disabled car’s engine block or chassis—away from the battery and fuel system (not the negative battery terminal) to reduce spark risk.
4. Energize and start. Start the donor car and let it idle for 2–5 minutes; lightly raise RPM to ~1,500 if safe to help charging. Try starting the disabled car. If it doesn’t start, wait another 2–3 minutes and try again.
5. Disconnect in reverse order and let it run. Remove the black clamp from the disabled car’s ground, then the donor’s black clamp, then the donor’s red, and finally the disabled car’s red. Keep the revived engine running for at least 20–30 minutes (preferably a drive) to recharge, or charge with a proper battery charger.

This sequence reduces the chance of arcing near the battery and helps protect sensitive electronics. Afterward, consider testing the battery and charging system to confirm the underlying issue is resolved.

Safety checks before you begin

These checks help prevent injury and costly damage, especially on modern vehicles with sensitive electronics, start/stop systems, and intelligent battery sensors.

• Confirm voltage and compatibility. Do not jump between 12‑volt and 24‑volt systems. Use only approved jump points if your car provides remote posts.
• Inspect batteries and cables. Do not jump a battery that is cracked, swollen, leaking, or frozen; call for service instead. Clean corroded terminals carefully and ensure clamps are secure.
• Avoid sparks. Keep metal clamps from touching each other. Connect the final black clamp to a chassis/engine ground, not the dead battery’s negative post.
• Protect electronics. Turn off accessories and lights. If available, use surge‑protected jumper cables or a quality jump pack.
• Environment and safety gear. Wear eye protection and gloves. Avoid flames or smoking. Jump‑starting in rain is generally fine if you keep connections dry and avoid standing water.

Taking a minute to confirm these conditions significantly lowers risk and increases the chance of a successful start without collateral damage.

If the car still won’t start

If the engine doesn’t crank or only clicks after several attempts, these troubleshooting steps can narrow down the cause and next actions.

• Recheck connections and contact points. Ensure solid metal contact, especially the ground point on the disabled car.
• Give it more time. Let the donor car run 5–10 minutes before retrying; a deeply discharged battery may need longer to accept charge.
• Try lights and dash indications. Total blackout suggests a connection issue; lights but no crank may indicate a bad starter, seized engine, or immobilizer problem.
• Listen for rapid clicking. This often points to a severely discharged or failing battery; consider a jump pack with higher cold‑cranking amps (CCA) or replace the battery.
• Consider the alternator. If the car starts then stalls or the battery light stays on, the charging system may be faulty—seek professional testing.

Persistent no‑start conditions often require a battery test and charging system diagnosis. Many parts stores can test both quickly, or call roadside assistance.

Using a portable jump starter instead of another vehicle

A quality lithium or AGM jump pack can be safer and more convenient than another car, especially for modern vehicles. The connection order is similar but follows the pack’s instructions.

• Charge and check the pack. Ensure it’s fully charged and rated with sufficient peak amps/CCA for your engine.
• Connect red to the disabled car’s positive terminal/post, then black to a solid chassis/engine ground.
• Power on the pack (if required), wait for ready indicators, then start the vehicle.
• Turn off the pack and remove clamps in reverse order once the engine is running.

Jump packs with spark-proof clamps and reverse-polarity protection reduce risk and are ideal to keep in the trunk for emergencies.

Special cases: hybrids, EVs, and start/stop systems

Not all vehicles handle jump‑starting the same way. The following notes reflect current industry guidance for 2024–2025 models, but always defer to the owner’s manual.

• Hybrids (HEVs) and plug‑in hybrids (PHEVs): You may jump the 12‑volt battery using designated posts; never attempt to jump the high‑voltage traction battery. Some hybrids require the car to be in a specific “ON/READY” state—follow the manual closely.
• Battery electric vehicles (EVs): Do not use an EV to jump another car. You can often jump an EV’s own 12‑volt system with a jump pack, but follow the manufacturer’s procedure to avoid damaging DC‑DC converters.
• Start/stop vehicles with AGM/EFB batteries: The jump process is the same, but replacement batteries must match type/spec. Many cars have an intelligent battery sensor on the negative terminal; always use a chassis ground for the final clamp.

Correct connection points and procedures vary widely by model. Using the wrong method can damage power electronics, so a quick check of the manual is essential.

Why the clamp order matters

Connecting positive leads first confines any accidental short to the positive circuit, while making the final connection to a distant chassis ground moves the inevitable spark away from hydrogen gas that can vent near a battery. Disconnecting in the exact reverse order breaks the circuit safely without exposing live clamps to one another.

Summary

To jump‑start a car, prepare both vehicles, connect red to positive on both cars, connect black to the donor’s negative and then to the disabled car’s chassis ground, start the donor and then the disabled car, and remove cables in reverse order—then drive to recharge. Verify compatibility, use proper ground points, and consult your manual, especially for hybrids, EVs, and start/stop systems. If the car still won’t start after proper attempts, test the battery and charging system or seek professional help.

Which battery terminal do you connect first when jumping?

When jump-starting a car, the first terminal to connect is the red (+) positive terminal on the dead battery. You then connect the other red (+) clamp to the positive terminal of the working car’s battery. Next, you attach the black (-) clamp to the negative terminal of the working car’s battery. Finally, you attach the last black (-) clamp to an unpainted, unmoving metal part of the dead car’s engine or frame, away from the battery. 
Step-by-step instructions for connecting jumper cables:

1. Position the cars: Ensure the working and dead vehicles are close enough for the cables to reach but not touching. 
2. Turn off both cars: Make sure both vehicles’ engines are off and keys are out of the ignition. 
3. Attach the red (+) clamps: Connect one red clamp to the positive (+) terminal of the dead battery. Then, connect the other red clamp to the positive (+) terminal of the good battery. 
4. Attach the black (-) clamps: Connect one black clamp to the negative (-) terminal of the good battery. 
5. Connect to ground: Connect the final black clamp to a clean, unpainted metal surface on the engine or frame of the dead car, away from the battery. This is a crucial safety step to prevent potential sparks that could ignite gases from the battery. 
6. Start the working car: Start the engine of the car with the good battery and let it run for a minute or two to allow the dead battery to begin charging. 
7. Start the dead car: Once the working car has been running, try to start the car with the dead battery. 

Remember to follow these steps carefully to ensure a safe and effective jump-start.

In what order do you jumpstart your car?

Here’s the correct order for your jumper cables:

1. RED to DEAD: Connect the red clip to the positive terminal on your dead battery.
2. RED to DONOR: Connect the red clip to the positive terminal on the donor vehicle’s working battery.
3. BLACK to DONOR: Same car!
4. BLACK to METAL: Back to the dead battery.

In what order should I jump start?

To jump-start a car, the jumper cable connection order is crucial for safety. Connect the red clamp to the positive terminal of the dead battery first, then the other red clamp to the positive terminal of the working (donor) battery. Next, connect the black clamp to the negative terminal of the working battery, and finally, connect the other black clamp to an unpainted metal surface on the dead car’s engine block away from the battery. Disconnect the cables in the reverse order.
 
Connecting the Jumper Cables

1. Red to Dead Battery: Connect the red (positive) clamp of the jumper cable to the positive terminal (+) of the car with the dead battery. 
2. Red to Donor Battery: Connect the other red (positive) clamp to the positive terminal (+) of the car with the working battery. 
3. Black to Donor Battery: Connect the black (negative) clamp to the negative terminal (-) of the car with the working battery. 
4. Black to Ground: Connect the final black (negative) clamp to an unpainted metal surface on the engine block of the car with the dead battery, away from the battery itself. 

Starting and Disconnecting

1. Start the Working Car: Start the engine of the vehicle with the good (donor) battery and let it run for a few minutes. 
2. Start the Dead Car: Try to start the engine of the car with the dead battery. 
3. Disconnect in Reverse Order: Once the dead car’s engine is running, disconnect the cables in the following reverse order: 
   • Black clamp from the engine block. 
   • Black clamp from the donor vehicle’s negative terminal. 
   • Red clamp from the donor vehicle’s positive terminal. 
   • Red clamp from the dead battery. 

This video demonstrates the proper way to jump start a car: 58sAAA Connect Video Hub | Auto Club GroupYouTube · Sep 23, 2024
Important Safety Tips

• Ensure both cars are turned off and the parking brakes are engaged. 
• Make sure the cars are close enough to reach but not touching. 
• Avoid contact between the positive and negative cables to prevent sparks. 
• If the dead car doesn’t start after a few tries, there may be a more serious issue requiring a mechanic. 

How do you jumpstart a car step by step?

And let it run for about 2 minutes then start the car with the dead. Battery. When it turns over let it run for 2 minutes then disconnect the cables in reverse.