When a APV indicates "shorted"... it's telling you that your build is below it's minimum allowable resistance... in this case, below the device advertized minimum of 0.3Ω.
Your build specs, per Steam Engine (see hyperlink siglines below), would indicate a 0.4Ω~0.5Ω net resistance, so the build, if it's accurate, is not your issue.
In general terms... to have a "shorted" atomizer display, you need either a dead short to ground, with a resistance of, in this instance, less than 0.3Ω. If you have a digital multimeter (DMM) or a ohm meter build box, you can measure the resistance of your atomizer build, interdependently from your APV.
To test the atomizer without benefit of a ohm meter, attach it to a non-regulated PV, like an 18650 mech mod, with a freshly charged battery. A high level of attention and caution is advised... in that if the mod immediately starts to get warm... the atty has a dead short, or your mech mod has a very high voltage drop/continuity issue... cease firing or carefully remove the atomizer from the mod - NOW!
It's possible that you have a shorted or otherwise faulty APV chipset, or a short in the 510 threaded connection... but to determine that, you'll need another, preferably 510 threaded, atomizer of a known resistance to test the APV.
