Mechanical Mod Won’t Fire: Troubleshooting Tips Check the Battery Welcome to eCig One’s comprehensive guide to troubleshooting a mechanical mod that won’t fire. So, if you find one day that your mechanical mod won’t fire, your device won’t do anything to help you troubleshoot the problem. The one thing that mechanical mods lack, though, is feedback. They’re also ideal for e-smokers who build their own atomizer coils, because they always output the full voltage of the battery to the coil - nothing is lost to wires and chips. Mechanical mods are prized by a subset of e-cigarette users for their low cost and simplicity.