This is a common issue among vapers, and it often occurs unexpectedly and without notice.
When your battery/display mod's screen says 'Check Atomizer' or 'No Atomizer,' it normally means it can't find the coil or can't read the coil correctly.
This may be a connection issue where the 510 connector on top of the battery/mod isn't making proper contact with the tank, coil, or pod, in which case it would say 'no atomizer.' If it says 'check atomizer,' it means the battery/mod can't read the coil, i.e. it can't fathom the resistance, or it detects a problem.
Here are some suggestions for resolving this vexing issue.
Step One - Clean all contact points
Remove the tank (or pod, if you have one) from your computer and clean all threads and connections carefully. This is normally done with a paper towel. On batteries and mods, there is normally one central pin, also known as a 510 pin; on pod kits, contact points should be visible under the pod.
It's normal to find dust, grime, and e-liquid on the contacts, which means you'll need to clean them on a regular basis.
Replacing your tank (or inserting your pod) on your battery/mod is easy. Make sure the tank is securely fastened, but not too tightly. If the problem persists, proceed to phase two.
Step Two - Reseat the coil
Remove and replace the coil in your tank. Occasionally, this miraculously solves the problem.
You'll have to disassemble your tank as you would if you were replacing the coil, which, depending on the setup, may be uncomfortable and messy if you have a complete tank.
When the tank is disassembled, unscrew the coil from the tank's base and clean the bottom of the coil where it screws into and makes contact with the tank. You'll also need to clean the tank's interior, including the area where the coil rests. Reinstall the coil and reassemble your tank until it's clean and dry.
If you're still getting 'check atomizer' or 'no atomizer,' it's time to try another (new) coil if you have one on hand; even an old or burned coil will suffice as long as the same error message appears.
To see if the error message is present without having to refill the tank, turn the power down very low if possible, and push the fire button for a fraction of a second to see the message displayed. If all is working properly again and you push the fire button for an extended period of time after installing a new coil, you can flame the new coil out and waste it.
If you're still getting the error message and haven't tried a new coil yet, now is the time to do so to with a more extreme and irreversible fault with your battery/mod.
Step Three - check 510 pin
If you're using a conventional mod and tank, make sure the 510 pin on the tank is connected to your mod. If it's adjustable, pull it out slightly and reconnect to the mod.
If you're using a sub-Ohm tank, make sure the coil's base is connected to the tank's base. You can usually do this by gently pulling the coil's base out, being careful not to snap the wires inside, and then reassembling the tank.
Step Four - try another tank
This is an excellent method for determining or eliminating the source of the problem. Simply swap them out if you have another tank on hand, or borrow one if you don't.
Feel free to go over the steps again to grasp the processes fully.