The Smart Clamp's smart switch has 2 settings. When pressed for about 1 second, the blue light turns on, thus engaging the Smart Clamp with the Power Bank. Pressing it the 2nd time for about 3 seconds turns on the green light. When both blue and green lights are on, the Smart Clamp is now ready to delivery the needed power to jump start your car. Nothing happens if the green light is not "ON'. This is one of the safety features of the Smart Clamp. For additional info, please visit this link: http://powerbankphils.com/ or our store at Lazada: https://www.lazada.com.ph/powerbankphils/?langFlag=en&q=All-Products&from=wangpu&pageTypeId=2