Welcome . When your Vamo says low volts ( means battery needs a charge )when it says 9.9 ohm , it means that your device ( atty , or carto ,) is not making a good contact with the connector in the top of the Vamo > You need to use a very small screwdriver , or ice pick , dental pick , or something similar , and gently pry up the contact plate , inside the connector . Not too much , just alittle . Maybe 1/16 of an inch . Or you can try a 510 adapter . Install that first , then screw your device into that . Have no idea , on the 0.0 ohm , as I have never seen that on my Vamo . Good Luck