How to Install a Secondary Fuse Box Quickly and Easily (Car Auxiliary Fuse Box)

If you have a ton of accessories (dashcam, gauges, footwell lights, auxiliary electronics etc) and struggle to splice into a power source or find a ground bolt every time you install something new, this mod is for you. This is a simple process that allows quickly and easily connect and disconnect accessories to their own fused power sources with no cutting or splicing required. Watch as I run through how to install a secondary accessory fuse box that runs directly from the battery but does not draw power when the car is off on my Legacy GT. You will need a fuse box, SPST relay, and some lower gauge wire depending on how much power you want to run to the box.

Things I used:

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[ClaytheBMXer]

Not sure if I missed it, but the power feed from the battery to the new fusebox should be fused at the battery at the amperage capacity of the fusebox with the accessories used. If the big positive cable running through the fender gets shorted, or one of the lugs on the box gets shorted (example: an accident), then your battery is directly shorted to ground! Cool video by the way!

[EZ-viewing.]

You’re a very well informed gentleman who does not mind sharing his experience. I’ve been searching for this a very long time. Thank you for your efforts.

[nuff]

As someone who's spent at least 100 hours trying to learn this shit from Google, even though I'm a visual learner, thank you. I get tunnel vision and struggle otherwise. So, seriously, I appreciate the video!

[coreyblitz]

What a man! Gotta love subaru people for always coming in clutch with clear answers for my questions.

[pujolshtr]

Thanks for the great video. This was exactly what I've been trying to find. A very simple explanation on how to install an extra fuse box for small accessories.

[chrisgraham]

You should note that the use of the relay allows the new fuse panel to only have power when the ignition is in the ON position. If you want power at the fuse panel continuously, no relay is required. More importantly, with or without the relay, you need a fuse in the power supply line from the battery. If you using #12 Awg wire off the battery, you need a 30 amp fuse installed as close to the battery as possible to protect that power supply wire from overheating and causing a fire. The wire size off of the battery and the fuse protection will depend upon the total number of amps drawn by the circuits of the panel.

[malachiclifton]

This is a nice high quality video that was very informative. I appreciate your straight forward explanations paired with your good videography of exactly what you were talking about.

[joemzd]

I gave you a thumbs up as soon as you corrected yourself from "just as good" to "just as well". Good job!

[losrodriguez]

I’ve have been looking for a video to add a fuse box like this without wiring a bunch of relays and had a hard time finding one. Thanks !!

[blackterminal]

Im working on a electric car project and this video was helpful to me for adding a fuse box. Thank you

[johnevans]

Absolutely perfect then I was a technician for Chevrolet for 10 years I know how to replace and repair anything on a vehicle up until 2016 but to be damned I could not figure out how where and why I could put my new fuse box that I added after adding two optimum batteries a 200 amp alternator and multiple accessories like backup camera Android touch screen radio front cameras and plow heated cameras so for when I'm filing and many other items with your simple advice and good ideas I was able to find the perfect spot in my truck where the wires reached easily looked gorgeous and did what I wanted to do thank you so much once the interior is done I'm going to take my beautiful truck which is not so beautiful now to the body shops maybe and turn her into a show truck

[luiso]

Awesome video! Ppl be sure to use his link in the description to purchase this product as a thank you! Thanks for making this video.

[dajur]

Nice video, this is exactly what I was wanting to learn. Thanks! I just wish there was a fuse panel with 2 fuse sections so that I could have constant power on 1 half and ignition power on the other. Well, I guess I'll be buying 2.

[stephenbrook]

This is excellent advice! I was watching this for my VAG car but i also have a legacy 😅
Thanks this will be great help

[draftnotion]

Great video, I am adding a wideband afr gauge and will do this for the power

[MUSTANGMAN]

I appreciate this video! I bought the exact same fuse box off Amazon so this helps!

[rameljeferuiz]

This is so cool, i want to add led lights to my 79 ford

[sorodaxu-]

You are a life saver. Thanks I appreciate your time and video. 👍

[zachster]

I'm a beginner. As in I watched like 2 other videos before you, so I had a slight understanding of what you're talking about, though I didn't catch what you meant by you led a wire through the fender and then for some reason your new fuse box has its own positive and negative to connect to and then I was confused why you even needed to do any of that when you have an interior fuse box, I've got a lot to learn, hopefully quickly lol

[bradleyhawks]

Very well put together video and easy to understand the info. Thank you!