Unique custom aux fuse panel

Mods impacted:

ARB DUAL Compressor - https://www.tacomaworld.com/threads/arb-bedside-compressor-mount.552331/
@mattgecko bed and underhood lights - https://www.tacomaworld.com/threads/fs-waterproof-under-bed-rail-led-lights-3rd-gen.391380/
Rear USB outlet - similar to this https://www.tacomaworld.com/threads/rear-usb-port-in-the-2016.397866/
BlackVue dash cam power circuit
15A Air Horn


I created what should be a one of a kind, unique to me, custom underhood aux fuse panel for my accessories. I wanted to show off the process, and explain where I started and where I am now.

When I bought my truck I knew I wanted to isolate any power use by my accessories so that they wouldn't be ugly tapped to existing fuses or get in the way of "core" vehicle needs. I also, despite common usage, hate the idea of grounding/completing circuits to the body metal of the truck. To that end I had browsed the TacomaWorld forums and found this thread (which I've also posted in) detailing some efforts to make aux fuse panels -- https://www.tacomaworld.com/threads/wiring-an-aux-fuse-block-relays-and-switches-in-a-2016.401253/ in fact I had copied the majority of the parts and came up with my starting fuse box, and here's my link to how it originally looked - https://www.tacomaworld.com/threads...witches-in-a-2016.401253/page-7#post-14563489

After upgrading a few circuits, relays, and the ARB Dual compressor I realized I hated how the box looked. It stood out as 'different' and 'alien' in the engine bay. It also blocked access to the OEM fuse panel if it was ever necessary to access it.



I bought a few replacement parts that I felt were more OEM looking and searched for a new fuse panel home. Fully aware that there are prefabricated brackets and panels I could buy, I wanted to make something that looked more OEM to me, and also gave me the flexibility of using relays (or not) as well as isolating power for my ARB compressor that I have mounted in the bed of the truck. What I decided on was to use the empty space in the passenger side of the engine bay (Automatic, 4x4, TRD OR) and make a completely custom bracket solution. All I had to do was remove the Denso alarm chirp and move it elsewhere, which ended up mounted to the bolt you see on the right side in this picture:


I started with the standard CAD layout (Cardboard Assisted Design) on a guesswork cut sheet of 12G steel and my first attempt at hand bending.



I then cut holes where I wanted my components to be, and tried to plan out fit and finish.



Realizing how absolutely much I hated that I couldn't fab it in a manner that I'd like, I then spent (slow learner) at least 12 hours in Fusion 360 designing the bracket (with bends) and sent it off to OSHCUT (https://oshcut.com) to laser cut out of a sheet of stainless steel for me.



I then mocked up placement, along with edge guards to prevent wire wear, and drilled holes and spray-painted.



I then installed the components and hand-wired and cut and crimped and shrink tubed the wiring for the bracket.



I then spent another 6 hours removing the old fuse box, extending any wire runs that were too short, creating a new run from the factory circuit to signal when ignition was on / off for my relays, and wiring a new 16 AWG line to the bed for my @mattgecko bed lights and my own custom SMARTCAP LED light strips. I also used this time to run a video cable to the bed for my BlackVue rear cam.



At this point it was go time - Here's my installation and wiring progress.



Lastly, after it was installed, even with the fancy bends to keep it rigid, the weight still caused the fuse panel to move up and down. Looking at the area and available mounting points, I was able to use brackets that came with the relay box to MacGyver up a support arm that connects to an empty hole on the air box. It does not wobble any more.




Parts / tools links:

Relay/fuse box:

$22 True Mods 12V DC Auto Waterproof Fuse 5-Pin Relay Box Block [6 Bosch Style Relay Holder] [6 ATC/ATO Fusible Holder] Universal Relay Block Box for Automotive Vehicles Cars Marine Boat Light Equipment

https://www.amazon.com/gp/product/B07MR64XK1

Dual Bus Bar:

T Tocas 100A Heavy-Duty Module Design Power Distribution Block Busbar Box with 12 Screws 4 M6 Terminal Studs

https://www.amazon.com/gp/product/B07DN92HVB

Distribution Junction Block:

Power Distribution Junction Block - 8 Terminal 12V Bus Bar with Insulator Boot and Protective Disc - Made in The USA (Red, 3/8)

https://www.amazon.com/gp/product/B09B17PXD5

Circuit Breaker:

$48 Bussmann CB185-100 100 Amp Type III Circuit Breaker

https://www.amazon.com/gp/product/B00139FQSS

#8 16-14 AWG Ring connectors:

$22 Wirefy 130 PCS Heat Shrink Ring Terminals #8 - a Resistant Ring Connectors - Eyelet Wire Connectors - Blue 16-14 AWG

https://www.amazon.com/gp/product/B08BLLBLRT

Wire Lugs:

$22 Wirefy 120 PCS Tinned Copper Wire Lugs Kit - Battery Lugs - Crimp Battery Cable Ends - Ring Terminals - 10-4 Gauge

https://www.amazon.com/gp/product/B08BYZ2HQK

Hand Wire Crimpers:

$46 iCrimp Ratcheting Crimping Tool Set 8 PCS - Quick Exchange Jaw for Heat Shrink, Open Barrel, Insulated and Non-Insulated Ferrules AWG 20-2

https://www.amazon.com/gp/product/B08DRCRRCQ

Hydraulic Wire Terminal Crimper:

$45 HYCLAT 10 Tons Hydraulic Crimping Tool Battery Cable Lug Terminal Crimper with 9 Pairs of Dies, 12 AWG to 2/0 AWG Wire Crimping Tool

https://www.amazon.com/gp/product/B06XR8BY65

Wire Marking Zip Ties:

EDSRDRUS 144pcs Zip Tie Tags in 25x15mm Zip Tie Labels Self Locking Zip Tags, Multi-Color Nylon Cable Ties with 216 Labels and 3 Maker Pens

https://www.amazon.com/gp/product/B099922NWG

Edge Guards:

$14 Universal Car Door Guards 33Ft(10M), Rubber U Shape Edge Trim Protection Strip, Black No-Glue Design Fits Most Vehicles

https://www.amazon.com/gp/product/B07MCZ4PXS

Wire Source for quick disconnects and smaller wire: https://wirebarn.com
Wire Source for heavy wire: https://wireandcableyourway.com
Metal cutting / bending: https://oshcut.com

 

Very nicely done.

 

Looks Good!!! Where did you get the Red Wire Loom?

 

Wow, nice work!

 

Great job, amazing patience. I'm jealous.

 

It was generic wire loom from Amazon as well.

$20 Xuniea 96ft Wire Loom Braided Cable Sleeve Covers Cord Management with 127 Pcs Tube Heat Shrinkable for Audio Video Cable Cord Protectors from Pets(1/4, 1/2, 3/4",Black and Red)

https://www.amazon.com/gp/product/B09F3CZG22

 

It looks like you have the positive distribution block running directly from that 100a breaker.

This is not best practice

You should have a protection device rated for the smallest wire every time you drop wire size

The large wire may be able to handle 100a, but if any of the smaller wires between the distro block and relay/fuse box short to ground...well you will have a lightbulb!

Also, you should have a fuse as close to the battery as you can get.

The custom bracket is sick, nice work!

Here is a really usefull chart for fuse sizing
http://assets.bluesea.com/files/resources/newsletter/images/DC_wire_selection_chartlg.jpg

 

Great work. Nice and clean. I will likely go to a sealed relay box like this when my blue sea panel rots out and gets corroded...again.

I agree with everything you said, but he's only running those wires like 4-5 inches from the distribution block to the relay box, where the circuit is fused for the smaller wire. To me, this is really no different then using an inline fuse on a 14g wire directly to the battery, like many people do for lights and accessories before they head down the fuse panel route.

Not sure how OP would get around this with his choice of relay box since it doesn't have provisions for larger gauge power and ground, like some other sealed boxes do. I'd definitely put my 100a breaker closer to the battery, if possible, or add another one.