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LED, Color Changes, Custom Lenses, whatever

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 #393497  by LUNAT1C
I've mentioned before that I've been working on an auxiliary relay center for my car off and on the past few years, and have kicked it in higher gear this year. I posted on my main images thread, but over here it should be more visible to those who might be interested.

Why would someone want to add an additional relay center? This practice is somewhat common in the offroad community, where 4x4s get additional accessory lights, winches, air compressors, etc and require a clean and tidy way of adding these accessories with a control switch in the cabin. Otherwise you wind up with a rats nest of power and ground wires, fuses, relays, cluttering up the engine bay and passing dozens of wires inside the vehicle for a bunch of random switches.

On my car I have added a number of circuits, including one outside the car, and wanted to get ahead of it before I got that same rats nest condition going on.

In 2019 I did some searching for small solutions to add as many as 5 circuits, and came across an extremely detailed how-to on Tacoma World. This how-to was of course tailored to current model Tacomas with the aforementioned goal of adding circuits for lights and winches, but the principle is the same so long as the busbars, relays, fuses, and wires used are suitable for the circuits intended. Given I will only be using RGBW LED bluetooth controllers, my needs are small.

From that Tacoma World how-to I settled on the Bussmann RTMR 5-relay setup. It's capable of having 5 fused relay circuits, as well as 5 fused non-relay circuits (total 10). I will only be using relays as I want the circuits to be powered from the battery and switched on only when I push a button inside the car, so I have spare fuses in the empty slots.

The switch bank was custom built in 2019, and I followed Keith's lead by adding them below the steering wheel. The result is a very clean installation that would normally not be noticed by the average person. They are blue LED lit switches, get indicator light power from the car's interior light circuit (lit only when the cars lights are on), and they only get power from the accessory circuit to pass to the relays. They only pass power when the ignition is on, eliminating any possibility of leaving something on and walking out to a dead battery.


They're wired to a molex connecter behind the knee bolster, so the bolster can be easily removed if needed (came in handy when I had to do the evap a few months later). Then a separate harness passes through the firewall, containing only one wire per circuit, up to the relay center. Power for the circuits does not pass through the switches, they only supply a small 3-5A signal when pushed to the relevant relay. The relay passes power from the battery and fuse to the circuit, hence only small wires are needed and the bundle thickness passing through the firewall is minimal.

Next, the Tacoma thread went into spectacular detail on building the RMTR, pinning it and making jumper wires, using the right pins and the right weatherpack seals. I finally got around to building it last year once we settled into our house and I had built a custom workbench in the basement for my tinkering.

I neglected to grab a picture of the unit itself, will add one later.

Now, I could simply fab up a mounting bracket and install it in the car at this point. But, I don't like things that look like they don't belong. The only space I have available is the space between the passenger strut tower and my cone air filter, which is also somewhat protected from direct engine heat. I took measurements of the area and then hit the yard, opening the hoods of a dozen different models before coming across a recent Stratus R/T sedan. I believe it was a 4-cyl, not sure, but the relay center service the entire car was the perfect size. I snipped all the wires and removed the relays and fuses (yard charges extra for loaded relay boxes) and took it home.

First order of business was to take it apart (3 sections, the base, the midsection containing the busbars relays and fuses, and the cover) and get out my multi-tool to gut it.

Here it is separated and gutted, busbars and relay socket section cut out:


Then I traced out the bussmann, ground busbar, and the Stratus relay box on a sheet of plastic that I had used in 2018 to make a new heatshield, and cut out a new platform for the bussman and ground busbar to attach to.

Here is the new plate, bussmann unit, sitting inside the Stratus box(nothing attached yet):


Cover installed. In addition to the KnuKonceptz fuse holder for my audio system being attached at the front below the air filter, this is really all anyone will see. I have since cut out the harness guide since it was interfering with the strut tower, and removed the mounting structure near the battery + input (the stratus' jump point) to make it fit better. The plan is for the battery input to enter at the Stratus' jump point, and for the switch harness, accessory circuit wires, and ground pass through the original Stratus harness point, where it will all be kept neat beneath the fender.


Mockup fitment in the car, you can see on the left where I am using the factory fender attachment point for the original air cleaner resonator assembly. That bit is plastic-welded to the base of the relay box. Next I need to work on a second attachment point, and add some foam to restrict vibrations against the strut tower:


Once all attachments are finalized, I will clean up the individual pieces, and paint the bottom and midsection flat black. The cover I am undecided on. My factory relay center cover is currently sanded smooth and painted body color with my Luna logo, with 2K clear. Leaving this one factory might be misleading with the note about the jump point (I'd rather continue using the factory LH jump point) and it wouldn't match the original relay cover and the plenum. I may belt-sand the lettering away, paint DSB and clear it, and add a Special badge to it. I would likely plastidip the red jump point cover. We'll see.

Then I would only need to finish pinning the switch harness, install the base on the car, make all my connections, and snap it together. Plan is to have this done for Carlisle. Maybe even have it ready to mount to the car for the CEMA show on 6/10 (not necessarily functional yet).
Sneke_Eyez, First Lady, StealthM and 1 others liked this
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 #393508  by First Lady
Very clean Robert, nicely done!!
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 #393514  by FIREM
Typical quality build with attention to detail, as expected by you :D
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 #393531  by LUNAT1C
I managed to get something like a sinus infection about a week ago that's still throwing me down like a sack of potatoes, but I've gotten on it whenever I'm not blowing my nose and finding how I can relieve the pressure...

I've got a makeshift screw boss attached that seems to be relatively good. Using Steelstik, I have it surrounding a nylon spacer that's longer than the battery door U-nuts and drilled enough for the screw to easily get in and out, and shaped into a square to prevent rotating it's way loose from torque and vibrations. I drilled a hole in the unit so the Steelstik is captive. Plan to wash the base and use epoxy to finish it off.

I also added strength to the plastic-welded fender attachment, and added a mounting plate for my audio systems fuse holder. Finally, added epoxy to the inside to add some strength to the custom mounting plate for the Bussmann unit.

Next is washing all the parts and painting black, then attaching the Bussmann and ground busbar and making my final connections.

Then figuring out what to do about prettying up the cover. Plan is to belt sand the letters off and sanding the grain away, then spray adhesion promoter, DSB, and 2K clear. Question is, do I leave the Fuse and Relay letters and paint them silver, or a custom badge? Undecided.
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 #393532  by FIREM
My first reaction was the last image using the “Wings” but you have the “New” Chrysler wings on the trunk. Is the new version with the blue lettering available in the smaller size?
That would be the ticket IMHO
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 #393533  by LUNAT1C
FIREM wrote: May 23rd, 2023, 5:49 am My first reaction was the last image using the “Wings” but you have the “New” Chrysler wings on the trunk. Is the new version with the blue lettering available in the smaller size?
That would be the ticket IMHO
I have several of that version in the "airbag" size, cut from various 200s over the years. I do like the wings the best, it's not used underhood yet.

I have the new version on the trunk and I've been back and forth about keeping it or finding a new condition "period correct" version (05-10) with the wax stamp. Grille has the wax-stamp version that I updated a new wax-stamp (which may clash), and steering wheel is that style. This mini-wing here I just had laying around and is too worn to use, I'd have to scrounge to find a good one or hope I find a good condition van door panel with one next time I go yarding.
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 #393556  by LUNAT1C
I think we're about ready for paint on the bottom and middle sections.

Lower mount epoxied for extra strength, both pieces smoothed up and sanded, and the positive bolt given some Dremel love to clean it up. I'll use a wire wheel on it to clean it up some more.

Both sections need to be washed and degreased after the epoxy cures, then paint.

On the mid section and lower part where all the components mount, I test fit them and drilled out where necessary for easy fitment, and confirmed one last time it all fits together.

RTMR and ground busbar (opposite side) installed, spare audio system fuse holder dry fit.
All that will be visible. Even the fuseholder will be out of the way, under the air filter.
After that, I will need to rearrange where my Bluetooth controller and lighting wiring is, cut down and pin the harness on the vehicle side, wire up the ground busbar, install positive jumper harness and ground cable run to the factory body point, and run a power cable from the unit to the factory jump point, and snap/ screw it all together.

June 10 is the CEMA show, should be installed then. Then finish the cover for Carlisle.
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 #393656  by LUNAT1C
Hopefully the order I placed last night is the last bit of components needed to finish this off. The base and midsection are both painted, and the relay center and ground busbar are mounted, wired, heatshrunk. Waiting on a few 4-ga cable lugs for 3/8" bolts to be able to finish off the main power and ground cables, then I can mount it all and wire up the signal connector and my existing BT controller to be the first system connected to it (uses Deutsch connectors, which I don't have pigtails for).

I may install the box tonight without full wiring simply to have a spot to mount the audio system main power fuseholder for the show tomorrow, just screw it in and clean up the cover as it is. One those lugs arrive I can get it the full power and ground, pop out the headlight to finish that connector, and be off and running. I can spend the next couple weekends as I get free time modifying the cover to match the plenum and factory PDC. There is light at the end of the tunnel!
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 #393693  by LUNAT1C
Something here technically doesn't belong... Can't put my finger on it...
Dry fit was a success, seems to be pretty sturdy as long as it's not pressed on. Got it together and apart again without any drama.

Tonight the last bit of cable lugs came in and I put together the power and ground cables and the harness for the first circuit (BT controller for the demon eyes and grille strips, and eventually engine bay lighting). Also sanded down the cover after the show at the former Chrysler museum Saturday.
All that's left is getting the headlight out, removing the single relay and wiring I have there now, and pinning the other side of the switch harness. Replace my current main battery ground with a new 1/0, hook up the power and ground for the relay center, and snap it all together! And paint the cover of course. I should have everything done and cover curing by the weekend.

Then pick an emblem for decoration and call it done.
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 #393697  by StealthM
That came out really nice. looks OEM to me....
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 #393730  by LUNAT1C
And… now it’s installed and working!

Yesterday I got the fascia loose and pulled out the headlight, removed the temporary relay and wiring I was using for the Diode Dynamics BT controller, and set about with the new wiring.

- Cut the switch harness down to size and pinned the connector, cut down the tech flex and heat shrinked it
- Ran the power and ground cables for the new relay center to their positions and bolted them down
- Trimmed up and installed the new 1/0 battery-to-body ground cable, replacing the factory run and the 4ga run I added in the “Big 3” many years ago. Strangely the spark show when I connect it to the body seems a lot stronger than I remember…

Then tested it, and presto! Nothing worked. Come to find out I missed one piece of the puzzle, I forgot to connect the second busbar in the Bussmann RMTR to the ground strip. So, I had to remove the system and main cables and went to the hardware store this morning for the closest I could find to the correct terminals to fit the studs on the Bussman and the ground strip, and made a small jumper wire for that connection. Hooked it up to my power supply to check (which I should have done before), and everything was working as expected.

Back in the car, reconnected it all, and now I can control that BT controller from the switch bank just as before, but with a much cleaner installation that enables me to add more accessories down the road if I choose with minimal fuss. Hardest part is working the midsection of the unit up to make the power connection, after installing whatever the accessory is and running the main leads up to the relay center.

All that’s left is remounting that BT controller since I had to move it, paint the cover, and put the air filter back on. I was hoping to have the cover painted this weekend, but as I was painting it I found some deeper scratches still very visible and I ran out of PBW spray paint. I’ll need to get more palm sander sheets and order more paint, either from O-Reilly or PBW is a made-to-order color only at this point. Hopefully there is still time before Carlisle, otherwise I’ll have to hit the yard for a spare cover while I wait for the paint.

Overall, very happy right now, even if I have issues at the other end of the car right now.

Side note: I found another possible option for a base unit that looks factory. While yarding yesterday morning, I came across a 1st gen LHS, with a fuse and relay center that seems like it would also work. Also mounted over the strut tower, so its base slopes for more room. Then there was a 4-relay box I found in a different Sebring a couple weeks ago that might work for a more compact system.
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 #394095  by LUNAT1C
Done! It's been painted, clear coated, and an emblem applied to jazz it up a bit. Success!
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 #394100  by FIREM
Looks like it was there from day 1 !
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 #394156  by Sneke_Eyez
Love it, it looks great under there!
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