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Old 12-11-2015, 08:47 PM   #1
Sandtrap9072
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Wiring Kc Lights and other accessories

So i am wiring up a set of kc lights and some other accessories.I don't want to wire everything into the fuse box because it seems like a fire hazard. I would like to have some sort of separate junction block for accessories that i would like to add to keep a nice clean look. My question is what should i use, and where should it be mounted? In the cab, or in the engine compartment. Any help would be greatly appreciated.
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Old 12-12-2015, 03:31 PM   #2
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Re: Wiring Kc Lights and other accessories

I wouldn't add anything into the fuse box inside the cab either. Everything is powered through the same 10/12 awg wire going into the cab, and with it running the headlights, heater fan, and everything else it is probably overloaded.

The way I did it and the way several FJ Cruiser and Jeep guys did it was to buy an additional fuse box. Like this here: http://www.cooperindustries.com/cont..._Tns_15300.pdf.

This uses weather pack style connectors, the newer style mini fuses, and you can buy them with or without the relay slots. On my truck, I set up the headlights to be relayed through the box and used the original wire as a signal wire in the fuse box.
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Old 12-12-2015, 04:00 PM   #3
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Re: Wiring Kc Lights and other accessories

Ok, i was thinking using something like this http://www.summitracing.com/parts/rfw-gw16/overview/ and branching into different circuits like this.
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Old 12-12-2015, 04:59 PM   #4
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Re: Wiring Kc Lights and other accessories

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Ok, i was thinking using something like this http://www.summitracing.com/parts/rfw-gw16/overview/ and branching into different circuits like this.
Any circuit you add, must be protected with a fuse. That junction block you posted has no provisions for fuses. I used an underhood fuse panel from a Cavalier. very nice compact item, and because it's OEM, good quality.
What's great about these panels is that the pin slots are all the same distance apart, so just by moving pins around you can use up the relay slots for fuses.
http://www.ebay.com/itm/2004-Chevrol...-/131310432314
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Old 12-14-2015, 03:53 AM   #5
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Re: Wiring Kc Lights and other accessories

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Any circuit you add, must be protected with a fuse. That junction block you posted has no provisions for fuses. I used an underhood fuse panel from a Cavalier. very nice compact item, and because it's OEM, good quality.
What's great about these panels is that the pin slots are all the same distance apart, so just by moving pins around you can use up the relay slots for fuses.
http://www.ebay.com/itm/2004-Chevrol...-/131310432314
x2 on the fuses. I wish you could take those fuse boxes apart. My original plan when I did the wiring on my truck was to get something like that but I wanted to terminate my wires directly in the box for a very clean look.

That cavalier box could be done nicely if you heat shrink all the wires and put some wire loom over them.
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Old 12-14-2015, 08:36 AM   #6
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Re: Wiring Kc Lights and other accessories

Definitely use a fused block...........also for hi amp accessories like KCs......always use a relay rather than wiring directly thru a switch.
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Old 12-14-2015, 12:27 PM   #7
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Re: Wiring Kc Lights and other accessories

I like these little auxiliary fuse blocks. They are simple with 1 hot wire going in (I normally put an inline fuse or circuit breaker to it).
Got 1 on my truck now (mounted under center console area) & used them on several vehicles in the past (under hood on top of inner fender) with zero problems. The one without cover can be found at AutoZone or wherever. The one with cover comes from marine place, like Bass Pro store or Overton catalog.
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Old 12-14-2015, 01:08 PM   #8
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Re: Wiring Kc Lights and other accessories

So, i shouldn't go the junction block route then. Not even if i circuit protect it? All i want is an area where i can splice into power, every circuit will be fused and relayed.The Kc Supplied harness is fused and has a relayed already. Seems like ill have a lot fuses.
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Old 12-14-2015, 06:29 PM   #9
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Re: Wiring Kc Lights and other accessories

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So, i shouldn't go the junction block route then.
I would mount another fuse box like one shown above as close to the battery as possible, and run all your aftermarket accessories from it. The original fuse panel is not designed to handle high current loads that are added to it. Think of it like a pony panel you would add to your house if you needed more circuits.
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Old 12-28-2015, 08:30 AM   #10
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Re: Wiring Kc Lights and other accessories

Ok, i got the new fuse box added. now i want to protect the fuse box itself. What size fuse-able link should i use?
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Old 12-28-2015, 10:22 AM   #11
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Re: Wiring Kc Lights and other accessories

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Ok, i got the new fuse box added. now i want to protect the fuse box itself. What size fuse-able link should i use?
How far away is the new fuse box from the battery?If it's within a foot, I would connect it directly. Any further then I would use a maxi-fuse, not a fusible link.
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Old 12-28-2015, 10:24 AM   #12
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Re: Wiring Kc Lights and other accessories

it is approx 3 to 4 ft.
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Old 12-28-2015, 10:25 AM   #13
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Re: Wiring Kc Lights and other accessories

What size fuse should i use?
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Old 02-18-2016, 09:27 AM   #14
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Re: Wiring Kc Lights and other accessories

So, id like to get your opinion on how i wired power to the fuse box. Instead of wiring directly to the battery,and have hot all the time. I decided to take and splice into the ignition switch so the added fuse box is only hot now when the ignition switch is on. In between the splice into the ignition switch and fuse panel i added a 30amp fuse. Please see attached picture and let me know what you guys think.
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Old 02-18-2016, 10:01 AM   #15
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Re: Wiring Kc Lights and other accessories

Quote:
Originally Posted by Sandtrap9072 View Post
So, id like to get your opinion on how i wired power to the fuse box. Instead of wiring directly to the battery,and have hot all the time. I decided to take and splice into the ignition switch so the added fuse box is only hot now when the ignition switch is on. In between the splice into the ignition switch and fuse panel i added a 30amp fuse. Please see attached picture and let me know what you guys think.
NO!!!

You are now drawing all of the current from all lights, accessories, etc through your switch, not good. You will have increased resistance on all your accessories which means dimmer lights, more heat, etc, your switch will get hot and go bad prematurely, or worse.

If you want the fuse panel to be powered with the ignition switch you will want to wire a relay in.

So it would go like this:



Wire from battery +, 30 amp fuse inline within 18" of battery, to pin 30 on relay.

Wire from pin 87 to the fuse panel

Pin 85 to ground.

Wire from ignition switch + to pin 86. This will switch the relay and the fuse box "on" when you turn the ignition on. It takes very minimal draw to engage the relay.

Also, what gauge wiring are you using? Hard to tell from the picture, but some of it looks rather small for the loads you are running.
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Old 02-18-2016, 10:35 AM   #16
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Re: Wiring Kc Lights and other accessories

Ok, so i can splice into the switch but should use a relay to do so? my power wire to the fuse box i believe is 8ga. i guess i am confused on where pin 30 comes from. What gauge should i be using?
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Old 02-18-2016, 11:42 AM   #17
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Re: Wiring Kc Lights and other accessories

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Ok, so i can splice into the switch but should use a relay to do so? my power wire to the fuse box i believe is 8ga. i guess i am confused on where pin 30 comes from. What gauge should i be using?
Yes, use the ignition switch as a trigger for the relay. Pin 30 comes directly from the battery. If you are using 8ga that should be plenty for the feed to the panel, it just looked smaller from the picture. For 30A, 10 ga is recommended usually.
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Old 02-18-2016, 12:12 PM   #18
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Re: Wiring Kc Lights and other accessories

Can you verify how i marked this diagram up? I think i am on the same page as you. How would you attach to the battery?
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Old 02-18-2016, 02:09 PM   #19
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Re: Wiring Kc Lights and other accessories

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Can you verify how i marked this diagram up? I think i am on the same page as you. How would you attach to the battery?
I would go 8 from the battery to pin 30, as well as 8 from pin 87 to the fuse panel.

85 and 86 do not have to be that heavy, 18 or 20ga is plenty as neither will be seeing much of any load as it is only the switching coil.

Just attach to the battery with a ring terminal.
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Old 02-18-2016, 02:13 PM   #20
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Re: Wiring Kc Lights and other accessories

Thanks for all your help, you've made it very clear to me!
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Old 02-20-2016, 10:40 PM   #21
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Re: Wiring Kc Lights and other accessories

So i made it back out into the garage tonight. Got a decent amount done. But have a few questions. Getting ready to wire back up the coil and was wondering where i should be getting b+from to the coil (red wire in picture)? Can i get it from the fuse box, and should it be a constant b+ or hot only when key is on? I guess originally how was it powered? Secondly, the green wire is for the tach, but if you notice they are two different gauges. what am i supposed to do here, doesn't seem right to take and wire the two different gauge wires together. any help would be greatly appreciated
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Old 02-21-2016, 10:28 AM   #22
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Re: Wiring Kc Lights and other accessories

Coil should be hot with key on only......otherwise it won't shut off with the key after you start it.
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Old 02-21-2016, 04:17 PM   #23
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Re: Wiring Kc Lights and other accessories

Common Sense....stupid question, thanks!
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Old 02-22-2016, 06:15 PM   #24
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Re: Wiring Kc Lights and other accessories

Can any of you help me out with the tach wire gauge issue?
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Old 02-22-2016, 09:44 PM   #25
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Re: Wiring Kc Lights and other accessories

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Getting ready to wire back up the coil and was wondering where i should be getting b+from to the coil (red wire in picture)? Can i get it from the fuse box, and should it be a constant b+ or hot only when key is on? I guess originally how was it powered?
The coil needs power with the ignition switch in both the 'run' and 'start' positions. You can plug into the fuse box 'IGN' (ignition) receptacle.

Or if you want to make it more like the factory configuration, run a 12ga wire from your HEI connector over to the bulkhead connector on the driver side of the firewall. Install a Packard/Delphi 56-series male connector onto the end of your 12ga wire.

Then locate the special cloth-covered resistance wire that used to power the old points ignition coil. With the bulkhead connector unplugged, squeeze it's terminal edge-wise and extract it from the connector (it pulls out through the wire entry side). Finally, insert your new wire/terminal in it's place and plug the connector back in.

Quote:
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Secondly, the green wire is for the tach, but if you notice they are two different gauges. what am i supposed to do here, doesn't seem right to take and wire the two different gauge wires together.
That's just a signal wire for the tach. Since there isn't very much current flowing through that wire, the gauge isn't overly important.

But if you want to avoid an inline splice and have the same gauge wire for the entire length, you can extract the terminal and it's short pigtail wire from the connector. Then install a Packard/Delphi 56-series female terminal onto the end of the wire that comes from the tach and insert it directly into the connector.
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