Show off your aux fuse panels.

Exactly. I ran some extra #10 wires into the cab (there’s a grommet under the driver’s seat) from my engine bay mounted bracket with its ground buss, stand alone 40A fuses and RTMR. The RTMR is nice and compact and being sealed as well as containing relays & fuses works great for exterior accessories but was a poor fit and overkill inside the cab.
With this set up only switch wires penetrate the cab for exterior accessories and only power supply& ground do so for interior accessories. Probably the best resource for this topic is this thread
https://www.tacomaworld.com/threads/diy-build-and-install-a-bussmann-rtmr-fuse-relay-block.399454/
Pretty much everything I’ve done is informed by this and the thread we’re in now.

 

As a best practice it is always better to run a real ground connection from aftermarket accessories back to the battery ground. This helps avoid noise issues or locally pulling up potential in a weak local ground path. Not everybody adheres to this as it takes extra work, but it does help minimize noise and ground loop problems etc.

https://en.wikipedia.org/wiki/Ground_loop_(electricity)

 

That's the thread that started it all. I built a packed RFRM (RFMR?) based on that guide. Very thorough. The BOM alone would have been daunting without him.

Thanks for the knowledge bomb!

 

I think the RTMR is the smaller one and the RFMR is the larger one. I decided on the sub panel approach with additional panels to minimize wire congestion.

 

Yeah in retrospect I should've gone with the RTMR. I couldn't even fit enough wiring to occupy all the slots available on the RFMR. Not to mention, it's been installed for a 2 years now and I haven't added any other accessories...yet.

 

Hopefully you’ll have many more years to add them.

 

You know it! You should see the setup someone made for their Uptop Overland roof rack. It's bonkers and I am trying to recreate it in a more limited scope.

 

Looking at this one for the simplicity of including everything and straightforward instructions



at what point does this mod become necessary?
Is the “threshold” 4 or more attachments?

so far I’ve got 3:
-rear aux lights
-hood light
-bed light
-headlightservices harness, might not count

it is more wires than stock, but not yet a birds nest

$30 catch can is blocking in the way, will need to figure out where to move it. Current spot was done finding a random hole and bolt on the side to put bracket/can

 

Blue Seas panel is nice if your relays are part of the accessories but there are fuse/relay combo panels as well that are often more compact. Bussman makes one but it’s not the only one. One thing they pretty much all share is a limit on the current in each circuit (~30A) so if any accessories need more those need to be individually fused with higher current relays.

 

Not done, but getting there, with a mounting plate from @paranoid56

 

Installed a few weeks ago. Already down to one open relay. Was a fun project. Learned a lot. May start building a Bussmann RMFR for more expansion.

 

Looks good. Is the tray only supported by the fender bracket on the right side? If so, any issues with vibration or warping?

 

Yeah, just attached to the fender. Pretty solid. Haven't had any issues.

 

the positive cable going to the circuit breaker could be helping to dampen smalll vibrations. mine basically acts like a brace

 

My tray is only 1/16” aluminum so I added a brace down to one of the fuse box mounts.

 

Finished.

GEP relay box, two 25A relayed circuits, one 20A relayed circuit, one 25A constant on circuit, 80A total for the box. All outputs terminated with DTP connectors, relay triggers with a DT connector.

 

Revision 4!
I had my gripes with Rev 3, had to get into the OEM Fuse box and, well because of some wiring stuff, wasn't able to get the cover off. Going back to what was the OG/ Rev1/ table saw plate that i had and going over.

Redesigned to be in 2 parts; French cleat thing and the mounting plate



Besides that, some minor adjustments done to the layout to give me a bit more room in some places. Used the same 6 peg bolt panel for connecting the relay box to new wires/ outputs.



Pretty hyped with how this turned out. No nuts included in the design, it's all just heat-set threaded inserts. Mix of M4 and M6s and the entire setup is printed in PETG+ on a Creality K1. Took about 7 hours to print the 2 parts separately and prepped for install.



Figured to see it's strength. Yeah super good enough, this panel will NEVER see this level of forces and if it does, there are bigger problems.


Old Rev 3 Panel layout

French cleat installed separately

Top plate slid under the old panel and into place.


Everything bolted into place;



had to trim off the black rain guard (just the rubber section) to get the wires to fit. a non-issue.



New clearance under the panel, easier to get to the 4x4 relay box now if needed.

 

Man... those GEP relay boxes are NICE. I'd love to redo my relay box with those

 

This is what I'm running. Nicely designed and simple. I love the breaker as it makes it quick to connect new accessories. Using mine to power some relays for aux lighting and was a nice place to mount the 4awg cable for my amp.



Also using all OE-style switches in a custom left-side panel from MESO.

 

I really like it, it's hard to say if it's nicer than a Bussmann RTMR, but I didn't need 5 relayed circuits and 5 constant on circuits for the 4Runner, so I went with the GEP, no regrets at all.