Before discarding the battery, perform the following steps to test if it is actually defective.
1. Check Your Battery to see if it is sufficiently charged. Place the e-cig in your mouth backwards—with the LED side in your mouth and blow into the e-cig. This activates the battery. If the LED light comes on, your battery is working and doesn’t need to be charged. If it doesn’t light up, try charging the battery.
OR if the tip of your battery is blinking several times (about 5 times or so) when you drag on it, it needs to be recharged.
2. If you’ve checked that your battery is charged, and you still get no vapor, you may have a dud or clogged cartridge. It’s possible for a bit of dried e-juice to clog the cartridge. Take the cartridge in your hand, with the thread side facing down. Tap it forcefully on a hard surface, like a desk. This can help redistribute the some juice for optimal vapor production.
If that still doesn’t work, take the cartridge, screw it onto the battery, and blow into it. Do not inhale, as you normally would: blow out. This will activate the battery and heat up the cartridge. You should be able to feel it getting warm. Once it gets hot, it should burn off anything that’s clogging it up.
3. If that still doesn’t produce any vapor try this: With the cartridge screwed on to the battery, keep the LED side of the battery in your mouth (about half to one inch) and then blow hard onto it a couple of times. You may or may not see smoke coming out of the other side of the cartridge. Now flip the e-cig and try taking 2 or 3 strong puffs. Flip the e-cig again, keep the LED side in your mouth and try blowing again a couple of times. Try this couple of times and see if that makes a difference.
4. If you still get no vapor, try the same battery with one or two different cartridges. If still no vapor is produced, try using another battery with those cartridges. Depending on the combination, you should be able to identify if it is the battery or the cartridge that is defective.
If you have identified that it is the battery that is defective and it is a new battery, it is most likely defective. If it is the battery that you have been using for a while, it may just need a good cleaning
Note: If you fill your own liquid in the cartridges, it is possible any extra liquid might drip into the battery and cause short-circuit. Anytime, you feel that the any drop of e-liquid might have dropped inside the battery, unscrew the cartridge from the battery, hold the battery from the LED side and shake it (with the thread side downwards) like a thermometer to discard any e-juice. Then, let the battery dry for about a day or two. Once the liquid has dried off, it is likely that the battery starts to work again.