Auxiliary fuse/relay panel (1 Viewer)

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Looking for an elegant solution to controlling your Auxiliary lights and other devices? Fog lights, off road driving lights, radio circuits, and any other high power device requires it's own wire harness. You can't just tap into any old wire you find that has 12 Volts in it. It becomes awkward and dangerous to add another wire to the mess on the positive terminal of the battery every time you add a new device. There are fuse blocks available from Blue Sea and others, but if you also have a relay in your Aux circuit, where do you put that?

With quality parts from major vendors, I have developed a weather resistant fuse/relay panel that can be mounted on top of a wheel well or on the inner fender wall in the engine compartment, and will serve as a central hub for 5 relay switched Aux circuits and up to 5 always on fused Aux circuits. You run only one wire to the battery and with your switches and wires, you can control up to 10 Aux devices (5 switched and up to 5 fused).

My Aux Panel can greatly simplify your wiring. There are only two color coded wires for each relay--a skinny wire and a fat wire. The fat wire is the wire you connect to your device. The skinny wire is the control wire and is connected to a switch that you provide. When you order, you will specify whether you want the relay to be activated when the control wire is switched to ground or when the control wire is switched to 12 volts (hot). Regardless of how the relay control is configured (switched ground or switched hot), 12 Volts is supplied to the fat wire of the same color (or shade thereof) when the relay is activated. That's all there is to it. Using my Aux fuse/relay panel will take the complexity out of wiring your aftermarket devices. See post # 11 in this thread for schematics and further discussion of the switched ground and switched hot option.

https://forum.ih8mud.com/merchandise-storefront/352802-auxiliary-fuse-relay-panel.html#post5240849

The main power lead is a 10 gauge 36 inch wire that is protected by a fusible link. Please specify if you will need to locate the fuse/relay block farther than 36 inches from the battery. Mounted on the brackets, the relay module is 5 inches tall, and at the base of the mount brackets, it is 7 inches by 3.5 inches. So a good way to test for fitment is to cut a 7 inch long piece of 2X4 and use that as a model. The main power lead can be lengthened up to 10 feet total length for an additional $10.

Each individual Aux relay circuit is protected by a 30 amp fuse and each non-switched wire is protected by a 15 amp fuse. The total simultaneous load on the relay/fuse module should not exceed about 60 amps.


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nice product
will keep it in mind for the future
good pricing too--- buying 5 fuse holders, 5 relay holders and 5 relays would end up over $50 pretty fast, a little extra for a neat installation seems like a fair price to pay.
 
Cool, wish wish I could trade my
various fuse holders and brakers.
 
Nice work. One quick question--

Would the wiring/circuitry be able to handle heavier loads? I'm considering wiring my aux lamps and my (as yet uninstalled) power seats. As in your OP, I'd rather not have a spaghetti of hot leads on my battery.

I don't know how much draw the seats take; I'm still working on finding the pinouts for them.

Also, might such a thing come with directions? I'm not a complete idiot when it comes to wiring, but have not yet mastered relays.

Truth be told, I'd buy the headlight harness that has the extra couple of circuits in it. I'm really only interested in wiring the above two devices at the moment.
 
The relays are 35 amp relays. You probably wouldn't want to continuously run them at that rate of current, but they are definitely high amp. They should handle your Aux lamps no problem. Your lamps probably are less than this, but twenty amps at 12 Volts would be 240 Watts (Watts=Volts X Amps). Twenty amps is about as much as I would routinely switch. If you have more watts than that, you would use more than 1 relay--ie banks of lights.

I designed the Aux panel to be very simple. There are two colored wires for each relay. The skinny wire controls the relay. You hook this wire up to a switch that will connect it to ground. When the skinny wire is grounded, the relay contacts close and 12 Volts appears on the big wire. The big wire (12 Gauge) is the one you connect to your load--fog lights, driving lights, etc. It is pretty simple really. You don't need to understand relay theory at all.

Power seats are a different animal. You typically want the relays close to the seats so you don't have to have long runs of fat wires. Also, every up/down or back/forth motion will take two relays, which can eat up 5 relays in a hurry. The Bussmann relay/fuse panel could be configured for this, but you would want to locate it near or under the seats. Do the seats not come with relays?

So if the fuse/relay module will primarily be used for lights, etc then you would mount it in the engine bay. If it will be primarily used for the seat, then you would install it under the seat. Or...you could buy two. :D

And yes, it will come with instructions and I am available to answer any questions.

EDIT: As an additional note, using the relay panel for power seats would require it to be configured differently than it is configured for the Aux panel. One relay panel could be configured for up to two directional seat motions which would use up 4 relays. That would leave one relay left over for the heated seats.
 
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clean looking product, will definetly keep these in mind.....

georg
 
That makes a lot of sense, thanks for the quick response. As far as the seats are concerned, I'm not sure either.

I picked up two seats out of a Bimmer 328 the other day to fit into the 60. I can see that they are power, but do not know yet if they have heat or not. Once I can find a pinout or something that tells me which wire is which, I'll head your way.

Thanks again--
 
Very nice, this is exactly what I've been looking for. Two questions.

What kind of relays are those, are they like the common type you can find in the store?

Is it possible to make one with AGC fuses? I'd like to keep the fuses common with the ones in the stock location
 
They are called micro relays and mini fuses, and are commonly available. The relays are rated at 35 amps. The fuse/relay panel is made for this style of fuse and relay. Any other type of fuse, such as the fuses in the vehicle fuse panel won't work. If you are worried about spares, I can provide you with as many as you want at a pretty reasonable price. These fuse/relay panels are made by bussmann for the transportation and vehicle market. Does that help?
 
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I have included 3 schematics for the 3 different ways the Aux fuse/relay block can be configured. There are three default options: Config A, Config B, and Config C.

Config A: In this configuration, the relays are turned on by switching the relay control wire to ground. This is the simplest configuration. There is no need to locate and tap into any vehicle wires for this configuration. However, if you wish to use switches with indicator LEDs in them, or if you wish for the relays to be disabled when the ignition switch is off, you should consider Config B or C.

Config B: In this configuration, the top three relays are switched on by 12 Volts that comes from the battery or ignition. The obvious advantage for an ignition activated/de-activated relay is that you won't run your battery dead if you accidentally leave something on. Any switches with an LED indicator will require this option. The bottom two relays are configured with switched ground just like all the relays in Config A.

Config C: All the relays in this configuration are 12 Volt switched. For Config B and C, I provide a 15 amp fused non-switched wire coming out of the relay module that you can use as a 12 volt source for the switches or whatever else you would like.
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Neato, I'll have to keep these in mind once I get all my dual battery stuff installed. :)
 
Each relay is turned on by grounding the control wire for the corresponding relay. [STRIKE]If you find an existing vehicle circuit that goes to ground when the ignition is turned on, and if you connect the control wire from the Aux panel to this circuit, then the corresponding relay would turn on with the ignition. This would provide 12 Volts to your radio when the key is on[/STRIKE]. Otherwise, you would need a separate switch that would ground the control wire to activate the relay.

Using this idea--[STRIKE]connecting a control wired from the Aux Panel to a circuit that goes to ground when the ignition is turned on[/STRIKE]--you could actually connect one relay to a power distribution block mounted under the dash. Then connect your low power devices such as a CB radio, GPS, cell phone, etc to the power block. All these devices would then have power when [STRIKE]the key is[/STRIKE] a dash mounted switch is turned on, and no power when it is off.

Then you could use the other relays for high power devices like fog lights, driving lights, etc and you would control these devices with a dash mounted switch that grounds the control wire for each relay.

Make sense?

EDIT: Upon further inspection of schematics for both the FJ60 and FJ62, there are no circuits that go to ground with the key in the ACC position. So, the option of an additional fuse block is still a good one, but you would turn it on and off with a dash mounted switch. Refer to post #11 for options.
 
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Each relay is turned on by grounding the control wire for the corresponding relay. [STRIKE]If you find an existing vehicle circuit that goes to ground when the ignition is turned on, and if you connect the control wire from the Aux panel to this circuit, then the corresponding relay would turn on with the ignition. This would provide 12 Volts to your radio when the key is on[/STRIKE]. Otherwise, you would need a separate switch that would ground the control wire to activate the relay.

Using this idea--[STRIKE]connecting a control wired from the Aux Panel to a circuit that goes to ground when the ignition is turned on[/STRIKE]--you could actually connect one relay to a power distribution block mounted under the dash. Then connect your low power devices such as a CB radio, GPS, cell phone, etc to the power block. All these devices would then have power when [STRIKE]the key is[/STRIKE] a dash mounted switch is turned on, and no power when it is off.

Then you could use the other relays for high power devices like fog lights, driving lights, etc and you would control these devices with a dash mounted switch that grounds the control wire for each relay.

Make sense?

EDIT: Upon further inspection of schematics for both the FJ60 and FJ62, there are no circuits that go to ground with the key in the ACC position. So, the option of an additional fuse block is still a good one, but you would turn it on and off with a dash mounted switch.

Another option would be to wire the primary power to the aux block with a relay and have the power feed the relay from the ignition. Here is my aux wiring setup on my fan however it should work.

https://forum.ih8mud.com/80-series-tech/326290-caution-idiot-wiring-need-aux-fan-wiring-help.html

Hope it helps.
 
Another option would be to wire the primary power to the aux block with a relay and have the power feed the relay from the ignition. Here is my aux wiring setup on my fan however it should work.

https://forum.ih8mud.com/80-series-tech/326290-caution-idiot-wiring-need-aux-fan-wiring-help.html

Hope it helps.

Yes, you could do that--use a separate relay to provide the path to ground for the Aux panel control wire instead of a switch. I almost included that idea in my previous post, but was a little concerned it might come across as confusing. So good to know someone else is thinking the same thing.
 
just got the aux box today in the mail. it was packaged very well and it is built even better. this is really a trick setup. the attention to detail is beyond what i had hoped. thanks so much for getting it out before my trip. i will post some pictures of my setup. thanks so much!
 
need to mark this post. I want to order this relay panel!
 
Got mine in the mail, Erik did a great job putting that thing together. Now I gotta start the arduous of running all the wiring to hook everything up now:frown:
 

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