Setting Up with an Add-a-Fuse Kit

For those seeking a more streamlined and effective installation, an add-a-fuse kit is an excellent choice. An Add-a-Fuse Kit, sometimes called a fuse tap or fuse adapter, is used to expand the circuitry in your car's fuse box.

Essentially, it allows you to add a new connection to an existing fuse or even create a new circuit in an empty fuse slot. Add-a-fuses may power any accessory or gadget—not just a dash cam—by inserting them into already-existing fuse slots.

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For everything you need to install a dash cam, purchase our Essential Installation Kit which comes with add-a-fuses & the fuses you need.

As for the Voltage requirements, the maximum tolerance of a fuse, or the greatest amperage of power it can withstand, is indicated by the number on the back of any fuse. The fuse will blow when this tolerance is exceeded, cutting off power to whatever it is attached to. These act as a shield for your connections, so that in the event of a power surge, your systems aren’t overloaded and fry, which would cause you to replace the entire system.

On the other hand, the ordering of the add-a-fuse is also crucial if you're connecting to an existing fuse. As your first line of defence, make sure the existing fuse goes on first, closest to the add-a-fuse's legs – this fuse needs to be larger or equal to the fuse you add after. It’s because all the power is going to go through this first fuse, both the original draw of the fuse, plus the added draw from your dash cam.

Then, the added fuse from your kit should go second, and should be equal or less than the original fuse. Take note: the only power draw that will go through this second fuse is going to be from your added connection, your dash cam or other device. While a large fuse is technically usable, it won’t really be protecting anything, as the first fuse will always trip first. If you’re using an empty fuse slot, simply put the one fuse tap in the first position.

Most importantly, please avoid using any of the fuse slots that are utilized by important parts of your car, like the engine modules and airbags. This is to prevent any worst-case scenarios, as if anything goes wrong, it’s important not to lose these core functions.

This video shows you how to attach a fuse tap onto your add-a-fuse, as well as using a crimping tool (ie. needle nose pliers) to attach the cables of your hardwire kit into it.

Firstly, gather the necessary tools for the installation – your dash cam’s hardwiring kit, an add-a-fuse kit, a crimping tool, and a circuit tester or multimeter.

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The hardwire kit comprises three wires: an accessory wire, a constant wire, and a ground wire. Note that the ground wire is typically black, while the functions of the yellow and red wires may vary based on your camera model. Check the label on each cable to ensure their functions.

To begin the installation, locate your vehicle's fuse box, commonly found under the steering wheel, in the glove box, or in the front footwell. In case of multiple fuse boxes, choose the one closest to your camera installation point. Some fuse boxes may have a panel or cover that needs to be removed.

After that, it’s time to select a suitable fuse slot. Safer options are those associated with non-critical components like the sunroof, radio, moonroof, or cigarette lighter, with easily testable functions. The cigarette lighter socket fuse, in particular, is a preferred choice for an ignition connection due to its minimal power usage and consistent on/off behaviour with the vehicle, which is easily testable, and generally idle.

Again, before committing to a fuse, test it with a multimeter or circuit tester both when the vehicle is on and off. Once you've identified proper ACC and Constant connections, proceed to crimp the hardwire kit wires to the add-a-fuses.

Next, use a crimping tool or needle nose pliers to trim the rubber tubing and expose the wiring on the hardwiring cable, so that some of the bare cable is showing. Connect the cable to the other end of the add-a-fuse, the plastic tube. Then, the metal sleeve of the connector is compressed around the exposed wire using a crimping tool. After crimping, apply some force to tug on the add-a-fuse from both ends and to ensure a tight connection.

Next, prioritize grounding the cable first to avoid electrical issues. Connect the black ground wire to an unpainted metal bolt in your vehicle.

Most cars have an obvious ground point near the fuse box, possibly already used by existing components. Loosen the bolt, attach the ground pincers, and then re-fix the bolt. If your ground cable is a full circle, you can fully remove the bolt before fixing the ground or even cut open the grounding circle.

Finally, put the add-a-fuse back into the fuse slot. Once all steps are completed, the add-a-fuse simply needs to be inserted back into the slot from which the fuse was removed.

To accommodate this higher power draw, connecting to a fuse capable of handling a heavier load becomes necessary, typically between 20A-30A. Given the battery's maximum draw of 9A, the secondary add-on fuse tap should be rated at 10A or above. It's advisable to utilize a multimeter to measure the active power flowing through the existing fuse already, ensuring that combining that initial draw with the draw of the battery does not surpass the fuse's limits and avoiding overloading.

Ideally, finding a fuse that experiences relative inactivity during daily driving is preferred. This allows the battery to have its dedicated fuse for drawing power. Additionally, our installer recommends starting off batteries to draw power on low initially, letting them run for a few days before increasing to high if necessary. This approach ensures a proper setup before introducing a heavier load to the fuse.