When the jumper cables are incorrectly connected, the polarity of the electrical system on the vehicle with the dead battery will be reversed for a few seconds. This can irreparably damage many of the sensitive electronic components that are common on todays vehicles, such as on-board computers and electronic sensors.

What happens if you connect negative to negative jump start?

Never connect the black cable to the negative (–) terminal on your dead battery. This is very dangerous, could result in a possible explosion. Make sure you follow the instructions in your owners manual when jumpstarting your vehicle. Every car is different.

Where do you connect the negative jumper cables?

The positive (red) cable should be attached to the positive terminals on each battery. The negative (black) cable should have one end attached to the negative terminal of the dead battery, and one end grounded.

What happens if you connect a battery wrong?

When the jumper cables are incorrectly connected, the polarity of the electrical system on the vehicle with the dead battery will be reversed for a few seconds. This can irreparably damage many of the sensitive electronic components that are common on todays vehicles, such as on-board computers and electronic sensors.

Why did my jumper cables catch on fire?

The single most common reason for melted jumper cables is a misaligned connection. Typically, the red cable clamps attach to the positive post, while the black cable should clamp to the negative post. If these are reversed, it will lead to electrical failure and cause the cables to melt.