Jump-starting a car is a common roadside emergency, but did you know there's a method that involves connecting the jumper cables in reverse? This technique, often called "reverse polarity jump starting," is less common and carries a higher risk of damage if not done correctly. This guide is intended for informational purposes only and we strongly advise seeking professional help if you are uncomfortable performing this procedure. Improperly jump-starting your car can damage your vehicle's electrical system.
Understanding Reverse Polarity Jump Starting
Standard jump-starting involves connecting the positive (+) terminals of both batteries and then the negative (-) terminals. Reverse polarity jump starting flips this process. It's crucial to understand that this method is generally NOT recommended unless you have a specific reason, such as dealing with a damaged positive terminal on your dead battery. It's considered riskier due to the potential for sparks and short circuits.
When Might Reverse Polarity Be Considered?
- Damaged Positive Terminal: If the positive terminal on your dead battery is corroded, damaged, or inaccessible, connecting to the negative terminal first might be safer.
- Limited Access: In some vehicles, accessing the positive terminal can be challenging. Reverse polarity might offer better access in these cases.
Disclaimer: Again, we emphasize that standard jump-starting is always the preferred and safer method. Only attempt reverse polarity if absolutely necessary and you understand the risks involved.
The Step-by-Step Process (Reverse Polarity)
This procedure is inherently riskier. Proceed with extreme caution.
Step 1: Preparation is Key
- Safety First: Ensure both vehicles are turned off. Engage the parking brakes on both cars. Wear safety glasses to protect your eyes.
- Gather Your Supplies: You'll need a set of jumper cables of sufficient gauge.
- Location Matters: Park the cars close enough to reach the batteries but far enough to prevent accidental contact.
Step 2: Connecting the Cables (Reverse Order)
- Negative to Negative: Connect one end of the negative (-) jumper cable clamp to the negative terminal of the GOOD battery (the working car).
- Negative to Ground (on dead battery): Connect the other end of the same negative (-) jumper cable to an UNPAINTED metal surface on the vehicle with the dead battery. This is crucial – avoid connecting directly to the negative terminal of the dead battery if possible.
- Positive to Positive: Connect one end of the positive (+) jumper cable clamp to the positive terminal of the GOOD battery.
- Positive to Positive: Connect the other end of the positive (+) jumper cable to the positive terminal of the dead battery.
Step 3: Starting the Vehicle
- Start the Good Car: Start the car with the good battery and let it run for a few minutes.
- Attempt to Start the Dead Car: Try starting the car with the dead battery.
Step 4: Disconnecting the Cables (Reverse Order)
- Disconnect the Positive Cables First: Remove the positive (+) jumper cables in the reverse order of connection.
- Disconnect the Negative Cables Second: Remove the negative (-) jumper cables.
Post-Jump Start Checks
After successfully jump-starting your vehicle, allow it to run for at least 15-20 minutes to recharge the battery. Monitor your car's performance for any unusual issues.
Why Standard Jump Starting is Preferred
Standard jump starting is preferred due to its lower risk of causing damage. Connecting the positive terminals first reduces the chance of sparking and short circuits. It also allows for a more controlled flow of current.
Conclusion: When in Doubt, Call for Help
While this guide outlines the reverse polarity method, it's essential to remember that standard jump starting is the safest and most recommended approach. If you're unsure about any aspect of jump-starting your car, seek professional assistance from a roadside assistance service or a qualified mechanic. This will prevent potential damage to your vehicle and ensure your safety.
