DIY - Build and install a Bussmann RTMR Fuse/Relay Block

Yup, only reason for multiple taps is if you want some always hot power for switches. You can tap the door lock fuse for that.

 

The draw to trigger a relay is super low, for standard coil type automotive relays...
This is from 12v planet:
"The current draw of the coil is not normally shown but is typically 150-200 mA"

https://www.12voltplanet.co.uk/rela...rrent draw of the,can indicate a damaged coil.

 

If you need more juice for high current switches then either run dedicated power from one of the 5 fuse only slots or use a relay and/or fuse to supply a smaller fuse panel for interior stuff like seat heaters. The extra panel makes sense once you have multiple high current needs so you run just one high power wire to that panel and draw from that.

 

For the Song Chaun relays we use in the Bussman it’s ~100mA but even at 200mA you be hard pressed to find space for enough switches to over draw the fuse tap.

 

Absolutley, you are correct. You could chain tons together and even then have to have every one on full draw at once to even come close to a problem

 

Well, been a while since I posted any updates. here is the 6 pin connector out of the Bussman RTMR.


On the 2016 Tacoma's the two wires used to be Green and White/Green. These have been replaced with Brown and White/Black. So I ran these up into Bluesea block connectors so I could create a pigtail cable that would connect the 6-wire from the Bussman, the White/Black and Brown and a Power from the one of the Fuse Only.


This is the pigtail - missing the power connector which I put in after this shot.


Here is the 9 wire connector that goes from the pigtail through the firewall into the truck cab. I still need to solder on the wire connectors to complete it.
Six wires from the Bussman RTMR, the Tan and White/Black and a 12v power wire (9 wires).


That cable connects to this - which allows all my switches to connect into this - the one circled in red is for the Qi charger - which I need to make longer (like 3').


The five buttons are the Bumper Light Bar, Roof Rack Light Bar, Grill LED Lights, Zombie Lights, Qi Charger.
The Front/Rear anytime camera has it's own Relay and switch cable.
I might switch out the Zombie lights for the ARB compressor button.

 

Looks clean. I finished v2 of my Bussman last month. My OCD is happy knowing the wiring is clean, organized and easy to troubleshoot should that be required in the future!

 

After a full four months of the Bussman RTMR project - it has drawn to a close. The interface cable is now in place, harness from the engine to the Cab tested - and working, zip ties locking it all down for vibration.


Harness from the engine to inside the Cab with it's switch pigtail harness. Each one tested.


Finally - switches plugged in - lower text showing up.


AAAAAAND... icons on top light up - and relays on Bussman RTMR click on (used a test harness built to show me it's switching on).
ALL GOOD - now all I have to do is put the lights on - and wire them up to the RTMR relays.


THIS Project is officially *COMPLETED* now. Now, onto the Anytime Front/Rear Camera Project. At least I have the button in place...

 

FWIW, I have found that CE Auto Electric Supply is a great source for the 10AWG TXL, by the foot. I ordered from them the first go-round, and am ordering from them again for a mistake on my part and for some 14AWG TXL to rewire my light lead.

Super fast shipping, ordered this latest one yesterday and was in USPS hands within three hours on a Saturday.

 

I'm currently out of the tangless 280 #12110853. I just did a trial fit of the tanged #12077413 in the Bussmann and it seemed to fit perfectly. Could it be used in a pinch?

 

Dunno, Customconnectorkits.com sells them by the each/$.

 

I have some on order, but it's been delayed. I need a grand total of the one to finish the box and put it in the truck.

I'd pay like $10 just to go drive somewhere local to get it.

 

I’d worry that it’s either not going to lock in or not be able to remove. On the connectors the release is in the terminal and on the Bussman the releases are in it and not the terminals. You can try it or you can delete the tang. It’s just tinned copper.

 

My package finally arrived yesterday and the Bussmann is complete. Now I have to move on to wiring the cab.

I'm asking here as well as elsewhere as to best practice in joining wires. This has all been very professional quality to this point and I'd like to continue that inside the cab. I ordered Molex connectors for ease of wrangling and changing stuff down the road, and I've got a handle on that part. Next part I'm looking at is the end to end wiring hookups near the switches, and splitting the add-a-Fuse into multiple runs.

The end to end, I'm wondering if I should do something simple like bullet connectors. Removable, easy.

The 12v ACC split, are T-taps still really the best choice after all this time? I wanted something streamlined and easy to wrap and insulate. I'm going from one wire at the fuse box that immediately has to be split in two. Then the ends of these runs have to get split again up to six times depending how many switches are on the back end. I'm kinda surprised that I haven't run across a connector from Molex or otherwise that would function as sort of a bus bar. I see some that are more meant for the audio world with 0-4ga wiring, but obviously I'm only dealing with 18ga wiring. Are there some heat shrink solder-free (or otherwise) connectors that could handle one 18ga wire going in, and six going out? I suppose I could reduce the wire down at the switch to what I think is only 22 or 24ga to help that.

 

I’ve only used t-taps but I’ve read some much prefer posi-taps instead for tapping the dash lights. Another way is to either get a set of matching m/f plugs for one of the stock switches to pull a jumper out or just the pins to repin the two terminals with an extra wire from each to supply the illumination. I have varying requirements and locations for actual switch power so a single tap wouldn’t work but given the knowledge gained by doing this there are plenty of options available.

 

For one set of switches I used a molex header plug and soldered one wire in a loop to each of the fixed pin terminals and then one wire from each switch to the matching connector for just that type of buss plug. Any connector could be done this way though.

 

For the green Toyota push switch connectors (tall or short, any of the aftermarket brands) you can get the terminals from Digi Key: IL-AG5-C1-5000 as well as spare plugs and matching connectors if you want to avoid using bullet connectors in line for each of the wires. To daisy chain the switches like Tacozord does you have to use smaller wire than 18 awg in order to get 2 wires in each terminal. Make sure you leave slack so that you have room to connect/disconnect the plugs if you need to pull any panels. You can arrange things so that you only disconnect one plug rather than every one of your added switch plugs(1 wire for each trigger plus the 3 for power, illumination +, illumination -) determines the size of the plug you need for a given switch bank.

 

I used 2 pin JST for all custom switch illumination since T’s can be had cheap and also pretty easy to make.

 

Yeah, after thinking about it for a few minutes I think I have a better idea of what you are talking about. I bought some daisy chain connectors to provide LED+/-, and if I would have been smart would have asked that the 12v power supply do the same thing. That's okay, allows for a switch to connect to constant on. The daisy chains use JST.

I'll get it figured out. It's a damn shame I have to order literally anything to do with connectors and terminals. I'd love to just hit up a store.