The correct and safest order to connect jumper cables is positive to dead, positive to good, negative to good, negative to ground. This sequence minimizes the risk of a dangerous spark near the dead battery, which can potentially release explosive hydrogen gas. The final connection should be made to an unpainted metal surface on the dead car's engine block or chassis, not the negative terminal of the dead battery itself.
Before you begin, ensure both cars are off, parking brakes are engaged, and the cables are untangled. Positive terminals are typically marked with a "+" and often have a red cover; negative terminals have a "-" and are usually black. After a successful jump-start, disconnect the cables in the exact reverse order: negative from ground, negative from good, positive from good, and finally, positive from dead.
Here is a quick reference table for the connection sequence:
| Step | Connection Point on Donor Car ("Good" Battery) | Connection Point on Disabled Car ("Dead" Battery) | Key Reason |
|---|
| 1 | Positive (+) Terminal | Positive (+) Terminal | Establishes the main circuit. |
| 2 | Negative (-) Terminal | Unpainted Metal Engine Block/Chassis | Provides a safe ground, avoiding sparks near battery. |
| 3 | --- | --- | Start the donor car, let it run for a few minutes. |
| 4 | --- | --- | Attempt to start the disabled car. |
| 5 (Disconnect) | Negative (-) Terminal | Unpainted Metal Engine Block/Chassis | Reverse order for safe disconnection. |
| 6 (Disconnect) | Positive (+) Terminal | Positive (+) Terminal | Completes the safe shutdown of the circuit. |
If the car with the dead battery starts, drive it for at least 15-20 minutes to allow the alternator to recharge the battery. If it doesn't hold a charge, the battery may be old and need replacement. Always consult your vehicle's owner's manual for any model-specific instructions.
