Ohio Woman Has 'Black and Bloody' Vape Juice Removed from Lungs Ciberate, 5 Packs 10ml Multi Fruit Vape Liquid for E Cigarettes, E Juice for E Cig Vape Starter Kits, (Blueberry + Cherry + Strawberry + Watermelon + Grape), No Nicotine : Amazon.co.uk: How to Fix the Most Common Problems With Pod Vapes Disposable vape, just three components but what it bugs me how does it know when it's empty. Led flashes when no juice is left but how? What makes led flash?