Is There an Order for Putting on Jumper Cables?

Yes—follow this connection sequence: red to the dead battery’s positive (+) post, red to the good battery’s positive (+) post, black to the good battery’s negative (–) post, and black to an unpainted metal ground on the car with the dead battery. Remove the cables in the exact reverse order. This order minimizes sparks near the battery, protects electronics, and follows what most automakers recommend for modern 12‑volt systems.

Safety Checks and Preparation

Before you connect anything, confirm both vehicles and the environment are safe. Proper preparation lowers the risk of injury, fire, or damage to sensitive electronics found in newer cars.

• Verify both vehicles use 12‑volt, negative‑ground systems (most modern cars do). If unsure, consult the owner’s manual.
• Inspect the dead battery: do not jump if it’s cracked, leaking, swollen, or frozen (a frozen battery can explode).
• Park close enough for the cables to reach but ensure vehicles do not touch; set parking brakes and shift to Park (or Neutral for manuals).
• Turn off all accessories (lights, HVAC, infotainment) and both ignitions; remove keys or turn off power on push‑button ignitions.
• Locate designated jump‑start posts if provided; many late‑model cars route jump points away from the battery, especially if the negative terminal has a battery monitoring sensor.
• Wear eye protection and remove dangling jewelry; keep sparks, flames, and smoking materials away from batteries.
• Keep cable clamps from touching each other or any moving parts.

These steps reduce risk and help ensure your jump start is efficient and safe for people and vehicle electronics.

Correct Order to Attach Jumper Cables (Vehicle-to-Vehicle)

This sequence is designed to keep sparks away from the dead battery and to protect both vehicles’ electrical systems. Follow each step carefully and make sure clamps have solid, clean metal contact.

1. Connect red (+) clamp to the dead vehicle’s positive (+) battery post or designated positive jump post.
2. Connect the other red (+) clamp to the good vehicle’s positive (+) battery post.
3. Connect black (–) clamp to the good vehicle’s negative (–) battery post or designated negative jump post.
4. Connect the final black (–) clamp to a clean, unpainted metal ground on the dead vehicle—such as a solid engine block bolt or chassis ground point—away from the battery.
5. Start the good (donor) vehicle and let it run for 1–3 minutes; lightly hold the RPM around 1,200–1,500 if safe to help charging.
6. Try starting the dead vehicle. If it doesn’t start, wait another 2–3 minutes and try again. Avoid repeated rapid cranks; allow brief cooling between attempts.

Grounding the final black clamp away from the dead battery reduces the chance of igniting hydrogen gas that may vent during charging, which is why this order is preferred by most manufacturers.

Removing the Cables: Reverse Order

Once the dead vehicle is running, disconnect in the reverse sequence to avoid arcing, then keep the revived car running to recharge the battery.

1. Remove the black (–) clamp from the ground on the previously dead vehicle.
2. Remove the black (–) clamp from the good vehicle’s negative (–) post.
3. Remove the red (+) clamp from the good vehicle’s positive (+) post.
4. Remove the red (+) clamp from the previously dead vehicle’s positive (+) post.
5. Keep the revived vehicle running for at least 20–30 minutes of driving (or idling if necessary) to recharge, but note that a weak battery may still need testing or replacement.

Reversing the order prevents accidental short circuits and reduces the chance of sparking near the battery.

Using a Portable Jump Starter (Jump Pack)

Portable jump starters are often safer and simpler than using another vehicle. Always follow the device’s specific instructions and ensure it’s charged.

1. Turn the vehicle fully off and switch the jump pack off (if it has a power switch).
2. Connect red (+) clamp to the vehicle’s positive (+) battery post or positive jump post.
3. Connect black (–) clamp to a clean, unpainted metal ground on the vehicle (not the negative battery post if a ground point is available).
4. Power on the jump pack (if applicable) and attempt to start the vehicle.
5. Once started, turn off the jump pack and remove clamps in reverse order: black (–) from ground, then red (+) from positive.
6. Recharge the jump pack after use; many packs require full recharge promptly to maintain capacity.

Jump packs limit the risk to another vehicle’s alternator and are especially useful for cars with sensitive electronics or when roadside help isn’t immediately available.

Special Cases and Cautions

Modern vehicles and certain conditions call for extra care. Check the owner’s manual when in doubt—manufacturers sometimes specify unique jump points or procedures.

• Stop‑start, AGM/EFB batteries, and battery monitoring sensors: Many cars have a sensor on the negative terminal; use the designated ground/jump post, not the sensor-mounted terminal.
• Hybrids and EVs: Never attempt to jump the high‑voltage system. Some hybrids allow 12‑volt jump starting via under‑hood posts; many EVs can be jump‑started at the 12‑volt system to power electronics but should not be used to jump‑start another vehicle unless the maker explicitly allows it.
• Frozen batteries: Do not jump a battery that may be frozen (often below about −10°C/14°F). Thaw safely first.
• Severe corrosion or loose clamps: Clean and tighten for solid contact; poor connections can prevent starting and cause arcing.
• Diesels and glow plugs: Allow glow-plug cycle to complete before cranking; they may need a bit more charging time.
• Security/immobilizers: Some vehicles won’t crank after a deep discharge until the key fob is recognized or systems reboot; lock/unlock the car and wait a minute.
• Repeated failures: If it dies again quickly, the battery may be at end of life or the charging system (alternator) may be faulty—have it tested.
• Donor vehicle protection: Avoid prolonged high‑load boosting; once the dead car starts, disconnect promptly to protect the donor’s alternator.

These nuances help prevent damage and ensure you’re using the safest method for your specific vehicle and situation.

Quick Troubleshooting If It Won’t Start

If the engine still won’t turn over after a few attempts, try these simple checks before calling for service.

• Recheck clamp placement and ensure solid metal contact; move the ground clamp to a different bare metal point.
• Let the dead battery charge from the donor for 3–5 minutes before trying again.
• Use thicker, quality cables (4‑gauge or better) if yours are very thin.
• Confirm the donor vehicle is running at a slightly elevated idle.
• If lights come on but no crank, the battery may be too far gone, or there may be a starter/immobilizer issue.
• For push‑button cars, ensure the brake is firmly pressed and the fob battery isn’t dead.
• With a jump pack, make sure it’s adequately charged and rated for your engine size.

If these steps fail, the battery may need replacement or there may be a deeper electrical or mechanical issue requiring professional diagnosis.

Summary

There is a correct order for connecting jumper cables: red to dead (+), red to good (+), black to good (–), black to an unpainted ground on the dead vehicle; then remove in the reverse order. Prepare carefully, use designated jump points on modern cars, and consider a portable jump starter for added safety. If problems persist after a proper jump, have the battery and charging system tested.

What order do I put jumper leads on?

Here’s the correct order for your jumper cables: RED to DEAD: Connect the red clip to the positive terminal on your dead battery. RED to DONOR: Connect the red clip to the positive terminal on the donor vehicle’s working battery. BLACK to DONOR: Same car!

Does it matter which order you put jumper cables on?

Yes, the order of connecting and disconnecting jumper cables matters for safety to prevent sparks, short circuits, and explosions from the hydrogen gas a dead battery can produce. The recommended order is to first connect the red (positive) cables to both batteries, then connect the black (negative) cables to the working car’s negative terminal and the dead car’s unpainted metal chassis. For disconnection, reverse the process by removing the black negative cables first, then the red positive cables. 
This video demonstrates the correct and incorrect ways to connect jumper cables: 1mStan CravensYouTube · Oct 9, 2018
Connecting the Cables (The Right Way)

1. Red to Dead: Connect the red clip to the positive (+) terminal of the dead car’s battery. 
2. Red to Donor: Connect the other red clip to the positive (+) terminal of the donor (working) car’s battery. 
3. Black to Donor: Connect the black (negative) clip to the negative (-) terminal of the donor car’s battery. 
4. Black to Ground: Connect the other black clip to an unpainted, unpainted piece of metal on the dead car’s engine block or frame. This is the final connection, which helps prevent sparks near the dead battery. 

Disconnecting the Cables (Reverse Order) 

1. Black from Dead: Disconnect the black clip from the ground point on the dead car. 
2. Black from Donor: Disconnect the black clip from the negative (-) terminal of the donor car. 
3. Red from Donor: Disconnect the red clip from the positive (+) terminal of the donor car. 
4. Red from Dead: Disconnect the red clip from the positive (+) terminal of the dead car. 

Why the Order Matters

• Safety: Connecting the final negative cable to a metal ground point away from the battery minimizes the risk of a spark igniting hydrogen gas from the battery. 
• Electrical Safety: Following this sequence helps prevent short circuits and potential damage to the cars’ electronic components. 
• Explosion Prevention: The last connection is made away from the batteries to prevent any sparks from igniting any potentially explosive gases. 

What happens if you attach jumper cables in the wrong order?

Connecting the Leads in the Wrong Order
Connecting the Cables incorrectly (positive to negative or vice versa), Reversing the order can cause a spark, which may lead to battery damage or even an explosion.

What order do I take off my jumper cables?

To safely remove jumper cables, be sure to do so in reverse order they were attached–disconnecting positive cable from each red clip first before removing any black clips.