The Correct Order to Take Off Jumper Cables

Remove jumper cables in this order: 1) black clamp from the grounded metal on the car that was jump-started, 2) black clamp from the negative (-) terminal on the donor battery, 3) red clamp from the donor battery’s positive (+) terminal, 4) red clamp from the positive (+) terminal on the car that was jump-started. This reverse-order removal minimizes sparks and protects vehicle electronics; below is a detailed, step-by-step guide and safety context.

Step-by-Step: The Safe Order to Remove Jumper Cables

The safest way to take off jumper cables is to reverse the order in which you attached them, starting with the ground connection on the vehicle that was dead. Follow these steps once the previously dead engine is running smoothly.

1. Remove the black (negative) clamp from the grounded metal on the vehicle that was jump-started (the last connection you made).
2. Remove the black (negative) clamp from the donor vehicle’s negative (-) battery terminal.
3. Remove the red (positive) clamp from the donor vehicle’s positive (+) battery terminal.
4. Remove the red (positive) clamp from the positive (+) terminal of the vehicle that was jump-started.

By removing the ground first and the positives last, you reduce the risk of sparking near the battery, which can emit flammable hydrogen, and help protect sensitive electronics from voltage spikes.

Before You Remove the Cables: Stabilize the Vehicles

Ensure both vehicles are safely positioned and the jump-started vehicle is idling steadily. Turn off accessories (lights, HVAC blower, heated seats) to reduce electrical load, set parking brakes, and keep cables clear of fans or belts. Many technicians keep both engines idling during removal; the key is that the jump-started car remains running and stable.

Why the Order Matters

Batteries can vent hydrogen gas; disconnecting a positive clamp first raises the chance a dropped or contacting clamp will create a spark close to the battery. Starting with the grounded negative on the jump-started car moves the first disconnection away from the battery’s gas zone and reduces the risk of short circuits through the chassis. Correct sequencing also helps prevent damaging voltage transients to modern control modules.

Common Mistakes to Avoid

These frequent missteps can cause sparks, component damage, or injury. Keep them in mind while disconnecting.

• Pulling a red (positive) clamp first, especially near the battery.
• Letting metal clamps touch each other or the vehicle body while still connected.
• Clamping the negative cable to the dead battery’s negative post instead of a solid, unpainted engine/chassis ground (unless the vehicle specifically provides a designated negative post).
• Smoking or creating open flames near batteries.
• Mixing up positive (+) and negative (-) terminals or cables.
• Working around moving parts (fans can start unexpectedly on modern cars).
• Trying to jump a visibly damaged, leaking, or frozen battery.
• Letting the vehicles touch each other during the process.

A careful, methodical disconnect avoids arcing and protects both the people and the vehicles involved.

Special Cases and Modern Vehicles

Newer vehicles and alternative powertrains may have unique procedures. Always check the owner’s manual if available.

• Remote jump posts: Many cars (especially with trunk- or rear-mounted batteries) provide under-hood positive and negative posts—use these and follow the same disconnect order.
• Batteries with sensors: Vehicles with an Intelligent Battery Sensor (IBS) on the negative terminal may require using a designated ground point rather than the negative post.
• Start-stop/AGM/EFB batteries: These systems are sensitive to voltage swings; follow the manufacturer’s connection points and steps.
• Hybrids and EVs: Do not attempt to jump the high-voltage system. Some allow jump-starting the 12V system at specific posts; consult the manual strictly.
• Lithium jump packs: Treat the pack like the donor battery—disconnect negative/ground first, then positives—following the pack’s instructions.

Manufacturer guidance takes precedence. If a vehicle provides specific jump terminals or sequencing, use them exactly as directed.

After the Jump: What to Do Next

Once the cables are off, help the recharged battery recover and confirm the charging system is healthy.

• Let the jump-started engine run for at least 15–30 minutes, preferably by driving, to replenish the battery.
• If the engine stalls or won’t restart shortly after, have the battery and charging system (alternator) tested.
• Watch for warning lights or electrical oddities; some systems may reset after low voltage.
• If the battery is 3–5 years old or older, consider a professional test or replacement.

Early testing prevents repeat no-starts and can catch a weak battery or failing alternator before you’re stranded again.

Summary

To safely take off jumper cables, disconnect in this sequence: black from the previously dead car’s ground, black from the donor’s negative, red from the donor’s positive, red from the previously dead car’s positive. Keep the jump-started vehicle running, avoid sparks, and follow any vehicle-specific instructions. Afterward, drive to recharge and, if problems persist, have the battery and alternator checked.

What order do you take jumper cables off?

To safely remove jumper cables, disconnect them in the reverse order you connected them, making sure to remove the black (negative) cable from the grounded metal section of the dead car first, followed by the black (negative) clamp from the donor car. Next, disconnect the red (positive) clamp from the donor car, and finally, detach the red (positive) clamp from the dead car’s battery.
 
This video demonstrates how to safely disconnect jumper cables after jump-starting a car: 59sDrivers Ed ZoneYouTube · Nov 25, 2020
Step-by-Step Removal Order

1. Disconnect the black (negative) cable from the grounded metal of the dead car . 
2. Disconnect the black (negative) clamp from the negative terminal of the donor car’s battery . 
3. Disconnect the red (positive) clamp from the positive terminal of the donor car’s battery . 
4. Disconnect the red (positive) clamp from the positive terminal of the dead car’s battery . 

Important Safety Tip

• Make sure the engines of both cars are off before starting to disconnect the cables. 
• Keep the two clamps from touching each other once disconnected to prevent sparks. 
• Run the jumped vehicle’s engine for at least 15 minutes to give the alternator time to charge the battery. 

When disconnecting jumper cables, which comes off first?

When you connect jumper cables, you start with the positive or red cable. Disconnecting starts with the negative. Whether you’re changing a car battery or jump starting one, stay safe and protected. Make sure you put on safety glasses and take off any jewelry.

What is the correct order of jumper cables?

To connect jumper cables correctly, attach the red (positive) clamps to the positive terminals of both batteries (dead first, then good), then attach the black (negative) clamps to the negative terminal of the good battery and an unpainted metal component (a “ground”) on the dead car. Remove them in the reverse order: first, the black clamp from the metal ground, then the black clamp from the good battery’s negative terminal, followed by the red clamps. 
Connecting the Cables

1. Red to Dead Battery (+): Opens in new tabConnect the first red clamp to the positive (+) terminal of the dead battery. 
2. Red to Good Battery (+): Opens in new tabConnect the other red clamp to the positive (+) terminal of the good battery in the working vehicle. 
3. Black to Good Battery (-): Opens in new tabConnect the first black clamp to the negative (-) terminal of the good battery. 
4. Black to Metal Ground: Opens in new tabConnect the final black clamp to an unpainted, non-moving metal component on the engine block or chassis of the vehicle with the dead battery. This avoids sparks near the battery, which can be a fire hazard due to gases it may release. 

This video demonstrates the entire process of connecting jumper cables, including the final grounding step: 56sLes SchwabYouTube · May 23, 2017
Starting the Vehicles

1. Start the Working Vehicle: Start the car with the good battery and let it run for several minutes to allow the battery to charge. 
2. Start the Stalled Vehicle: Attempt to start the car with the dead battery. 
3. Allow for Charging: If the car starts, let both vehicles run for at least 30 minutes to allow the alternator to fully charge the battery. 

Disconnecting the Cables (Reverse Order) 

1. Black from Metal Ground: Disconnect the black clamp from the unpainted metal component on the dead car. 
2. Black from Good Battery (-): Disconnect the black clamp from the negative terminal of the good battery. 
3. Red from Good Battery (+): Disconnect the red clamp from the positive terminal of the good battery. 
4. Red from Dead Battery (+): Disconnect the red clamp from the positive terminal of the dead battery. 

Which color jumper cable do you take off first?

Remove the black negative clamp from the ground of the vehicle needing the jump. Remove the black negative clamp from the assisting vehicle. Remove the red positive clamp from the assisting car. Remove the red positive clamp from the formerly stalled vehicle.