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

Thanks, just need to source some connectors that will allow me to run the switches in a row and at the same time allow easy replacement if needed. To bad these won't allow for switchbacks.

 

What? The switches have removable connectors. They're not hardwired with just wires hanging out the back. Just unplug the connector and hook up a new switch if a switch dies.

 

understood.

 

Nobody makes switch backs with loose pins for the small push switch but since 3 of the 4 wires are common to all of the switches you can bundle/crimp those into 3 sets connected to 1 wire each and reduce it to the number of switches plus 3. If you use the dash dimming circuit for illumination then 2 of those come from inside the cab and if you grab switch power from a fuse tap then only 1 wire from each switch ends up going through the firewall. Edit- OP includes a deducated ground wire back to a ground buss which is a good idea since many problems stem from poor grounding. This ground wire isn't necessary if you use the stock dimmer circuit, only if you have grounded accessories inside the cab or don't use the dimmer circuit to ground the switch leds. Any accessories outside the cab would be grounded to the busses located at the Bussman. End edit
One way to make the sets is by using a plug. Say you have 6 switches, you get a 6-way plugs and connect all of the common switch wires to one side and then daisy chain the feed to all the connections on the other side. You would then need 4 plugs, one for each of the power, illumination power, ground, and finally one for all the switch control wires. It's more tidy to just crimp and seal the 3 sets but easier to pull a pin from a plug than undo a crimped/soldered/heat shrink sealed connection. Since the switch bodies are universal that's unlikely but only if you're swapping a switch, other things can fit in those locations that don't have the same connector. My center console has 7 locations but 4 don't use the same connector, 2 seat heater controls, the AUX/USB port, and a 12V display USB charger, only the the 2 camera switches plus one remaining blank might use the common connector.
I just used Molex mini fit jr plugs for all the connectors, they're available in 2,3,4,6,10 pins.

 

If you don't have all your switches the plug idea makes it easy to add them later on as well, you just crimp pins onto the 4 wires and push each one into the appropriate connector. As long as your Bussman feed conduit has a wire for each possible switch location you're gtg.

 

i'll echo this statement. I've been around quite a few communities and boards in my day and this is one of the best, most comprehensive tutorials i've ever seen.

and as someone who loves to tinker and learn, i say thank you sir. This is going to keep me busy for awhile

 

Hey guys,

Just want to double check since I'm an electronics noob, for the switch backs/rear terminal housings, is this the correct piece to use for the female connector you put into it?

https://www.waytekwire.com/item/30079/Delphi-12052457-Metri-Pack-Female-Loose-Terminal-/

(depending on wire gauge I guess).

Thanks.

Also, great guide, planning to do this myself soon.

 

Switch backs just use female spade connnectors, this is why the toyota small push switch has no corresponding switch back, it uses a proprietary connector with leads.

 

Apologies if this was previously discussed, but what accessories are safe to run from the non-relayed side? I was planning on using the relayed side for my LED light bar, Driving lights, Air compressor, winch power. And the non relayed side for bed lights, rock lights, rear/back up lights and some under hood lights. (still waiting for a few more supplies and I start building!)

 

It depends on switched or unswitched and if switches are used, what kind. For just a power run whatever the wiring and the fuses that fit will allow such as awg10 for 40A. For one of the tall left dash switches, they are rated for 20A but for the toyota small push switch(center console switches) only 3A. Keep in mind the total simultaneous amp draw for the Bussman is 85A and the Blue Seas is 100A.

 

This should be a MUST read for anyone planning on doing any electrical add-on to there vehicle. This will eb going to to the top of the mod list.

 

Can anyone subbed on this thread help me locate where I can get a bracket to hold RTMR and breaker for my 3rd gen?
If that is not an option any longer share best possible areas to mount?

 

@paranoid56 has made trays for people. I don't know if he does 3rd gen or just 2nd gen.

There's also PowerTrays.com.

 

Try tacomapros.com

 

anyone sell a kit with all the components? I am a rather build this, but with the minimum order on the pieces, it prices it higher than buying one.

 

try @Sandman614

 

is there an option to do this with more fuses??

 

There's a larger 10 fuse/10 relay unit or you could add an additional fuse only box(4, 6, 8, 10 fuses) with another fuse or breaker feeding it. A lot of people do that anyway to have a fuse box closer to what it feeds. Such as another bussmann or fuse box in the bed with a secondary battery. In my case I put a small 6-way under the center console and sanded the tabs on the cup holder to ease access. I also split it so that 3 are always hot and 3 are ignition hot. Remote fuse boxes can allow you to substitute a single long heavy wire feeding several much shorter small wires and is one way to tidy things up.

 

I'm wiring up my switch panel. Does anyone see anything wrong with jumpering all my positives together and powering them with the add a fuse wire? I would also jumper all my grounds together. Just skipping the whole tapping into the pos and neg dimmer wires. Don't care if the switches don't dim. 6 @OTRATTW switches using a beautiful @Iggy switch panel. 18 gauge wire.

 

Their 5 pin switches. upper and lower LED lights. two pos (power to switch and LED) and two ground. The fifth is the power out to the relay to switch the relay to power the accessory. I am asking about jumpering the two pos and two neg, not the 5th pin to the relay Maybe I'm using the wrong lingo or misunderstanding your response (thanks for the response by the way @Blackout14 ). The OP tapped one pos and one neg to the dimmer wires to be able to dim the switches. I want to skip that all together and jumper both pos to the add a fuse and jumper both ground together. Hope that makes sense. It works with a 9v on one switch. see any issues doing it with all 6 and an add a fuse (power with ignition) for all 6? Different approach than the OP.