The Correct Order to Connect Jumper Cables

Connect the cables in this order: 1) Red clamp to the dead battery’s positive (+) terminal, 2) Red clamp to the good battery’s positive (+) terminal, 3) Black clamp to the good battery’s negative (–) terminal, 4) Black clamp to an unpainted metal ground on the dead vehicle (not its battery). This sequence reduces the risk of sparks near the battery and protects sensitive electronics.

Why the Order Matters

Modern vehicles generate hydrogen gas during charging and house delicate electronic systems. Making the final connection away from the dead battery moves any potential spark away from venting hydrogen and helps protect components from voltage spikes. Following the sequence consistently also prevents accidental short circuits and reversed polarity—both of which can cause serious damage or injury.

Step-by-Step: Connecting Jumper Cables

The following steps assume both vehicles use a standard 12-volt, negative-ground electrical system and that you’re using quality, undamaged cables. Park the vehicles so they don’t touch, engage parking brakes, turn off both ignitions, and switch off all accessories and lights.

1. Attach the red (positive) clamp to the dead battery’s positive (+) terminal.
2. Attach the other red (positive) clamp to the good battery’s positive (+) terminal.
3. Attach the black (negative) clamp to the good battery’s negative (–) terminal.
4. Attach the other black (negative) clamp to a clean, unpainted metal part on the dead vehicle’s engine block or chassis, well away from the battery and moving parts.

This order ensures the final connection—most likely to spark—happens away from the dead battery, reducing ignition risk from hydrogen gas and helping safeguard electronics.

Disconnecting: The Safe Reverse Order

Once the dead vehicle starts and runs steadily, remove the cables in the reverse order to minimize arcing and protect both vehicles’ charging systems.

1. Remove the black (negative) clamp from the dead vehicle’s metal ground point.
2. Remove the black (negative) clamp from the good battery’s negative (–) terminal.
3. Remove the red (positive) clamp from the good battery’s positive (+) terminal.
4. Remove the red (positive) clamp from the dead battery’s positive (+) terminal.

Reversing the sequence keeps sparks away from the battery and maintains a controlled, predictable current path as you separate the circuit.

Using a Portable Jump Starter

If you’re using a booster pack, follow the device’s manual, but the connection logic is similar: keep the final connection away from the battery when possible and verify polarity before powering the pack.

1. Turn vehicle ignition off; ensure the pack is off (if it has a power switch).
2. Connect the red clamp to the dead battery’s positive (+) terminal.
3. Connect the black clamp to a clean, unpainted metal ground on the vehicle (or to the pack’s negative lead if the device requires that configuration).
4. Power on the pack as directed and attempt to start the vehicle.
5. After starting, power off the pack (if applicable) and remove the clamps in reverse order: black ground first, then red positive.

Proper sequencing with a jump pack reduces sparking and protects the pack and the vehicle’s electronics from sudden current surges.

Important Safety Notes and Exceptions

Before connecting any cables, confirm compatibility and site conditions. The following reminders address common risks and special cases.

• Use only on 12-volt, negative-ground systems. Check your owner’s manual for approved jump-start points—many vehicles have remote positive and negative posts specifically for jump-starting.
• Hybrids and EVs: Procedures vary widely. Many should not be used to jump another vehicle, and some require special posts or steps. Consult the manual; if uncertain, call roadside assistance.
• Inspect both batteries and cables. Do not jump a leaking, cracked, or swollen battery, or one that’s frozen. Replace it instead.
• Keep clamps from touching each other or any metal surfaces while connected to a battery. Remove jewelry and avoid loose clothing near moving engine parts.
• No flames or smoking near batteries. Hydrogen gas can ignite.
• Ensure solid, clean connections. Brush away heavy corrosion; connect to bare metal for the ground on the dead vehicle.
• Do not let the vehicles touch. Keep accessories off during the process to reduce load and voltage spikes.
• If available, use cables rated 4-gauge or thicker for better current flow, especially in cold weather.

Following these precautions reduces the risk of injury and electrical damage while improving the chances of a successful start.

Troubleshooting if the Car Won’t Start

If the engine doesn’t crank or start after proper connections, try these checks before calling for help.

• Recheck clamp placement and contact; ensure the ground clamp has clean metal and the red clamps are on the positive (+) posts.
• Let the dead battery “sip” charge for 5–10 minutes with the donor vehicle running, then try again.
• Gently raise the donor vehicle’s RPM to around 1,500–2,000 to boost alternator output.
• Verify the gear selector is in Park (automatic) or Neutral (manual) and that the clutch is fully depressed.
• Rapid clicking suggests low voltage or poor connection; total silence may indicate a blown fuse, failed relay, or severely discharged/bad battery.
• If it cranks strongly but won’t fire, the issue may be fuel or ignition related—jump-starting won’t solve that. Seek service.
• Avoid repeated long cranking attempts to prevent overheating the starter and cables.

When basic checks fail, roadside assistance or a professional diagnosis is the safest next step.

Summary

Connect jumper cables in this sequence: red to dead positive, red to good positive, black to good negative, black to an unpainted metal ground on the dead vehicle. Start and, after the engine runs, remove the cables in reverse. This method minimizes sparks near the battery, protects electronics, and maximizes the odds of a clean, safe jump-start.

Is there an order for putting on jumper cables?

Make sure you have followed these steps in proper order: red clip from booster cable to positive terminals, then black clip from booster cable to negative terminals. Once all connections are made, start up your working vehicle and let it run for a few minutes before attempting to start your dead battery’s engine.

Do I connect black or red first?

When connecting jumper cables to a car with a dead battery, always connect the red/positive cable first to the positive (+) terminal of the dead battery, and then to the positive terminal of the working battery. The negative (black) cables should be connected last, with one to the negative terminal of the working battery and the other to an unpainted metal surface on the dead car’s engine block or frame to complete the circuit.
 
This video demonstrates how to safely connect jumper cables to a car battery: 51sStan CravensYouTube · Oct 9, 2018
Step-by-Step Guide to Connecting Jumper Cables:

1. Turn off both vehicles: Opens in new tabEnsure the ignition keys are in the off position in both the car with the dead battery and the donor car. 
2. Connect the red (positive) cable to the dead battery: Opens in new tabAttach one red clamp to the positive (+) terminal of the dead battery. 
3. Connect the red (positive) cable to the donor battery: Opens in new tabAttach the other red clamp to the positive (+) terminal of the good battery on the donor vehicle. 
4. Connect the black (negative) cable to the donor battery: Opens in new tabAttach one black clamp to the negative (-) terminal of the donor vehicle’s good battery. 
5. Connect the black (negative) cable to the dead car’s frame: Opens in new tabAttach the final black clamp to an unpainted, unmoving metal part of the engine block or frame of the car with the dead battery. A slight spark may occur, which is normal. 

Why this order?

• Red first: Connecting the positive (red) cable to both batteries first creates a complete circuit without completing the negative side. 
• Last connection to metal: The last black clamp is attached to an unpainted metal surface on the dead car’s frame, not the negative terminal. This minimizes the risk of sparks, as the battery releases hydrogen gas that could cause an explosion. 

What are the 5 steps to jumpstart a car?

How to Use Jumper Cables to Start a Car

1. Step 1: Park the Cars Safely.
2. Step 2: Turn Both Cars Off.
3. Step 3: Find the Battery Terminals.
4. Step 4: Connect the Red Jumper Cable Clamps.
5. Step 5: Connect the Black Jumper Cable Clamps.
6. Step 6: Jump-Start the Car.
7. Step 7: Disconnect the Black Cable Clamps.

What is the correct order to attach jumper cables?

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.