Mechanical mods are prized by a subset of e-cigarette users for their low cost and simplicity. 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. The one thing that mechanical mods lack, though, is feedback. 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. We’re here to help. Welcome to eCig One’s comprehensive guide to troubleshooting a mechanical mod that won’t fire.

Mechanical Mod Won’t Fire: Troubleshooting Tips

Check the Battery

When your mechanical mod isn’t firing, the first and perhaps most obvious troubleshooting step is to try a different battery. The batteries used in most mechanical mods are considered “dead” when they drop to about 3.2 volts. A battery discharged below this level may not be able to fire an atomizer coil and may, in fact, be unsafe to use. Swap out your current battery for one that you know to be fully charged and see if the mechanical mod fires. Because a mechanical mod has no display to supply information about the battery, many mech mod owners find it very helpful to use a battery voltage checker periodically.

If your mechanical mod has never fired, consult the instruction manual to confirm that the battery polarity is correct. In most cases, the negative terminal of the battery faces the fire button at the bottom of the mod. Although some mechanical mods will fire with the battery polarity reversed, doing so is potentially very dangerous because any damage to the battery’s wrapper could result in a hard short to the body of the mod. In the worst case scenario, a hard short to the body of a mechanical mod will cause severe electric shock and burning.

Check the Atomizer

A mechanical mod won’t fire if the atomizer has a problem. Some of the problems that might occur with an atomizer include damage to the coil or, if the atomizer has never worked with your mechanical mod, a center pin that doesn’t touch the top contact point inside the mod’s threading. The worst case scenario is a short in the atomizer, which we’ll discuss later. Try swapping in a different atomizer such as a mass-produced tank or a traditional cartomizer.

Adjust the Pins

Your mechanical mod may have as many as three adjustable pins: one for the bottom of the battery, one for the top of the battery and one for the atomizer. Often, the pins are reverse-threaded, so they come out when turned clockwise. You’ll want to adjust these pins so your mechanical mod makes firm — but not overly firm — contact with the battery and atomizer. Be warned that if you over-tighten, you could deform the top and/or bottom caps of the battery. In this case, you’ll need to dispose of the battery for safety.

An important note about hybrid mods: A hybrid mod is a device with a hole rather than a pin in the top cap. In most mechanical mods, the top cap includes a pin that touches the top of the battery and the bottom of the atomizer. In a hybrid mod, the atomizer pin goes through a hole in the top cap and touches the battery directly, reducing power loss and potentially improving vapor production. Hybrid mods are only safe to use with atomizers that have protruding center pins. If your atomizer doesn’t have a protruding center pin — or has a spring-loaded pin that moves when pushed — it could cause a short when used with a hybrid mod. In this case, the mechanical mod won’t fire. It may also become extremely hot as the battery begins to vent hot gas. This is also a case that will likely require disposal of the battery.

Hybrid Mechanical Mod Not Firing

A typical hybrid mechanical mod. Note the long stem at the bottom of the rebuildable atomizer, intended to touch the top of the battery directly.

Clean the Device, Battery and Atomizer

A mechanical mod can become quite dirty over time — especially if you flood your atomizer frequently. Dust, grime and e-liquid residue can form a film on the contacts of your device and atomizer and prevent good power transfer. In addition, some people have reported new mechanical mods that arrived from the factory with contaminants such as machine grease and metal filings. Clean your mod with a soft cloth and cotton swabs. Some people use a little water or rubbing alcohol — simply follow the best practice for the component that you are cleaning. Be certain, though, that your mod and all of its components are completely dry before attempting to use the device again.

Check the Fire Button

A mechanical mod uses resistance to keep the button away from the bottom of the battery when the device is not in use. Early mechanical mods used springs — and many less expensive mods still use them. However, the preferred method is to use two magnets inside the button. In this design, the magnets are positioned so that they push away from one another but aren’t allowed to touch when the button is fully pressed. A mechanical mod with a magnetic fire button has a very smooth action — the button shouldn’t wobble and should last a very long time.

If you have a mechanical mod with a spring-loaded fire button, check to make sure that the spring isn’t compressed from use. If your mechanical mod won’t fire but the button becomes very hot, there is a good chance that you need to replace the spring or the entire button. If you have a magnetic fire button, check to make sure that a magnet isn’t cracked or broken. Most mechanical mods contain rare earth magnets that don’t conduct electricity. However, some rare earth magnets may have a conductive coating. In this case, a broken magnet could potentially cause a short.

In addition, some mechanical mods simply have finicky fire buttons that require you to apply pressure to the exact center for the mod to fire. Many mechanical mods also have locking fire buttons for safety. If your mechanical mod isn’t firing, is the fire button locked?

Battery Amperage Limit

Whether or not you build your own atomizer coils, it is crucial that you understand the capabilities of your mechanical mod’s battery. Although an in-depth explanation of battery technology is out of this article’s scope, suffice it to say that you need to be aware of your battery’s capabilities. You should also be certain that your battery is genuine, as battery counterfeiting is rampant. The most popular batteries currently used in mechanical mods can operate under loads up to 35 amps. Most atomizer builds are no problem for a 35 amp battery. However, you could run into problems when vaping a sub-ohm coil on a lesser or counterfeit battery. Always use a resistance tester to check your coil builds, and familiarize yourself with Ohm’s law.

Critical Battery Flaw

Most batteries for mechanical mods are designed so the top post functions as the positive pole, while the rest of the battery is the negative pole. The positive pole is insulated, but the battery’s wrapper is the only thing protecting the negative pole. In other words, if the wrapper is torn or removed, any metal object touching the exposed metal portion of the battery will effectively be touching the negative pole and may cause a short. You should dispose of a battery that shows any sign of cosmetic damage. Other signs of a critical battery flaw include bulging, warping and becoming painfully hot to the touch.

A Word About Heat

Speaking of heat, we feel it is necessary to mention the point that your mechanical mod should never become painfully hot to hold. We’ve heard of some videos in which mechanical mod users hold their devices in towels to protect their hands from discomfort. If your mechanical mod is painfully hot, you are over-stressing the battery and need to change what you are doing immediately.

Short Circuit in Mod or Atomizer

A short circuit is any situation in which electrical current flows along an unintended path. A short circuit could result in a variety of negative consequences such as an electrical shock or battery explosion. Of course, a short could also cause a mechanical mod not to fire. We’ve already discussed situations in which a damaged battery or fire button could cause a short. It’s far more common, though, for faulty coil builds to cause shorts. If your mechanical mod won’t fire, check the atomizer with a resistance tester. If the coil build worked previously, it may simply be that the mod was bumped or jostled, causing one of the coil leads to come out of its post. If the coil build has never worked, a coil may be touching the drip well or side of the RBA.

Hot Spring or Fuse

If your mechanical mod has a top- or side-mounted switch, it may have a safety feature called a “hot spring.” In the event of a short, a hot spring collapses to break the circuit before the battery fails critically. At this point, the mechanical mod won’t fire because pressing the button will no longer complete the circuit. You’ll need to replace the hot spring before the mod will fire again. More importantly, though, you’ll need to correct the situation that caused the short to begin with.

If your mechanical mod has a bottom-mounted switch, a hot spring won’t work because its collapse would close the circuit rather than opening it. However, some mechanical mods include “VapeSafe” fuses instead. Like a hot spring, a VapeSafe breaks the circuit in a mechanical mod when the current is too high. If your mechanical mod won’t fire and has a VapeSafe fuse installed, you first need to correct the over-current condition. Depending on the VapeSafe model, the fuse will trip at around 6 amps. With a fully charged 4.2 volt battery, this means that the resistance of the atomizer can’t be lower than about 0.7 ohms. Of course, many people build atomizer coils at 0.5 ohms and even lower, so they don’t use VapeSafe fuses. If your mechanical mod doesn’t have one, though, we highly recommend using a fuse. It really will add an extra measure of safety.

If your VapeSafe fuse has tripped and you have the VapeSafe 1 model, you’ll need to replace the fuse. This is a single-use fuse that trips once and never works again. If you have a VapeSafe 2, the fuse will actually reset itself when you allow it to cool. However, the fuse eventually wears out, which means you’ll need to replace the VapeSafe 2 every several months.