What happens if I connect the jumper clamps with reversed polarity?

If the clamps are connected incorrectly, the backlit LCD screen will display the Battery Status Icon, Battery Voltage Indicator, and Clamp Icons, while the Alarm Icon, the '+' and '–' signs, and the Reverse Polarity Icons will flash and the unit will sound a continuous alarm. You must disconnect the clamps immediately, as turning on the Jump Starter Power Switch while clamps are connected with reverse polarity will cause permanent damage to the unit. Reconnect the clamps with correct polarity before proceeding.