Wiring lights to aux switches, using harnesses?

[Arrowbear Rider]

I bought three pairs of 3" amber lights (generic) and some Nilight's, a pair of 3" ditch lights with a 14" light bar, plus some rock lights (lights & harness not shown) and amber grill lights (connects to parking lights fuse, so not shown). I'm going to mount the 6 amber in the mod bumper three per side (15 amp aux) and the 2 Nilights white 3" (longer one shown below) as ditch lights on the "A" pillar. Light bar on a bull bar. All lights came with what looks to be nice wire harnesses.

Each set came with a nice harness complete with on/off switch, relay and have fuses and I'm hooking up to my aux switches.

My question(s): From what I've seen on install videos, I "ONLY" have to wire a hot wire to an aux switch wire of the correct amp and a ground, seems too simple and a waste of good harnesses? And yet simple also works for me.

Do I cut up these harnesses and butcher to use, using only the red and black wires? This gives me the lead wire from the switch to where it splits off to each light. I'm assuming 2 amps per 3" led and and the three white lights, (2) 3" & the 14" bar should be ok on a 10 amp, 4 ,mps for the 3" with 6 amps left for the small bar.

or save harness for someone else to use, I have extra ditch light mounts too, two pair the $25 kind on Amazon.

or

Do I just disconnect the power switch (cut off connection for another use, and wire the red/black to the aux switches and ground using the rest of the harness saving/including relay and fuse? Are redundancy in relays and fuses OK? Help or hindered to circuit?

If the answer is simple wire from the aux switches, one hot to switches and a ground, then I'm buying wire and connectors to simplify and will have two sets of ditch light brackets along with the wiring harness (four, one for three lights) I could trade/sell to pay for the new stuff.

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[Dmorty217]

I have the Nilight ditch lights and 30” led bar too and I just left the harness as is and zip tied them up. No real reason to do so but that’s what I did. Going to remove my ditch lights in favor of the oracle mirror lights as it’s less things randomly on the vehicle and a cleaner look. Way more expensive than the Nilights though. To answer your question is all you need is power to the aux switch wire and a ground to work.

 

[Baja Bronco]

I just walked another member through this via PMs, and he was happy his lights worked! Yes, your last paragraph is correct. Any lightning company, and I only run Baja Designs, they all include everything in the harness, relays, fuses, toggle switch. With the Ford Upfitter switches, they eliminate the need for the relay and toggle.

It’s just point to point, so yes you can use wire and forget the harnesses. I would recommend keeping the fuses in line, about 6 to 10 inches away from upfitter wire / ground, in the advent too much draw, wire gets hot, pops the fuse.

 

[Neigh]

Ford has already put the switches, relays and fuses in place with the aux switch setup. If it were mine I'd chop those harnesses down until they're just power and ground and take advantage of all the OEM wiring goodness.

 

[Arrowbear Rider]

To answer your question is all you need is power to the aux switch wire and a ground to work.

I would recommend keeping the fuses in line, about 6 to 10 inches away from upfitter wire / ground, in the advent too much draw, wire gets hot, pops the fuse.

Ford has already put the switches, relays and fuses in place with the aux switch setup. If it were mine I'd chop those harnesses down until they're just power and ground and take advantage of all the OEM wiring goodness.

Thanks guys, I'm going with wire directly to aux switches, but using the length after the relays with the splits and connectors to the lights; might make it all the way to the lights with just a small length added with the fuse.

The harness from Nilight has three connections, one for the bar and two for the 3" ditch lights, just need to determine if all splits are the same gauge or if the bar light is the separate wire and bigger. I should be able to see any difference once stripped.

For the three pairs of amber lights (going together in the mod bumper) I'm assuming I can run the three sets of wires, that came with the lights (cut out/after the relays) and combine before at the 15 amp aux switch wire? I would be using their wires without the relays and on/off switches for the correct gauge.

 

[Arrowbear Rider]

I have the Nilight ditch lights and 30” led bar too and I just left the harness as is and zip tied them up. No real reason to do so but that’s what I did. Going to remove my ditch lights in favor of the oracle mirror lights as it’s less things randomly on the vehicle and a cleaner look. Way more expensive than the Nilights though. To answer your question is all you need is power to the aux switch wire and a ground to work.

Any problems with the Nilight's wire harness? The one I got is 16 gauge to connect the two ditch lights, which I realized are 4" wide, 60w and the 12" bar is suppose to be 300w. The harness has a 15 amp fuse & 16 gauge says 13 amps, I was going to use a 10 amp aux switch.

I have the six 40w amber lights for total 240w. Which switch do I need to use?

These are all LEDs and am I correct that the wattage claimed is a estimate of what the equivalent of LEDS?

 

[helifino16]

It's just me probably, but if I had this to do all over again, I'd find a 6-port wiring block that would help me identify which wire goes to which switch. You can affix the block near an available ground point (to use for all) and then you can easily add/switch between different options.

Something like this:

I seem to recall someone else doing this and it looked way cleaner than what I have now.

 

[smiths65]

Anyone know what fuses 32-34 (Auxiliary power points[20A]) connect to?
Engine compartment fuse box...

 

[Dmorty217]

Any problems with the Nilight's wire harness? The one I got is 16 gauge to connect the two ditch lights, which I realized are 4" wide, 60w and the 12" bar is suppose to be 300w. The harness has a 15 amp fuse & 16 gauge says 13 amps, I was going to use a 10 amp aux switch.

I have the six 40w amber lights for total 240w. Which switch do I need to use?

These are all LEDs and am I correct that the wattage claimed is a estimate of what the equivalent of LEDS?

should of proof read my reply… 20” light bar I have hooked up to aux switch 5 with no problems. Ditch lights on 6. I used heat shrink water proof wire connectors, so no issues with connecting. As far as the amps are concerned, I didn’t take that into account. There are others with serious light bars that are pulling more than what any aux switch is rated for, seemingly with no issues. For whatever it’s worth I don’t use my lights much, they are blinding

 

[Arrowbear Rider]

should of proof read my reply… 20” light bar I have hooked up to aux switch 5 with no problems. Ditch lights on 6. I used heat shrink water proof wire connectors, so no issues with connecting. As far as the amps are concerned, I didn’t take that into account. There are others with serious light bars that are pulling more than what any aux switch is rated for, seemingly with no issues. For whatever it’s worth I don’t use my lights much, they are blinding

Thanks for the reply. One reviewer made a big deal about the gauge of the wires and yet everyone else seems to have had no problems.

 

[jharrell3623]

For the cost of a way to tell how much each light draws , its pretty senseless to not buy this and check the amps , and read up on wire size for correct and safe coverage. Just cause everyone jumps off a cliff , does not mean you should as well. Those Nilight products are actual wattage from what I experienced. The 4 inch Nilight pair I have are 60 watts each for an almost 5 amp draw per light. This is not an equivalent to incandescent thing with Nilight. If it says 300 watts. Then its going to draw about 23 amps on average 13 volt circuit. So the 240 watt array is going to be about 18 to 19 amps draw.
Here is the thing with wiring. Let say you use the harness built in by ford , and they have lets say 16 gauge wire. Refer to this guide for 12 volt systems.
Wiring amp loads
You can see clearly there is a risk of fire if that bar draws 23 amps and there is a 16 gauge wire running to the roof if that wire is 15 or so foot long. Its probably only about a 8 foot run but still risky.
I would say absolutely paramount that you get a tester like this to actually see the amperage its drawing.
Amp Tester
I have a feeling these cheaper chinese light companies are purposefully allowing a lot more power draw on the LEDs to brighten them up and get the Lumens WAY higher to compete with these other companies selling light bars for 1200 or more. My Nilights did draw 60 watts and a real 5 amps. Not equivalents.
The real issue is this , if you have a light bar on for a while. You do not notice anything the first say hour. Then the smell comes , then the short happens , then the fire starts. Now you could say at the point of the short , the fuse should blow but what about the wires behind the fuse that the insulation is burned off of now. They have no fuse protection. Now you got possible real issues.
I test the loads of each light , and do the math , and I actually OVER size the wire by a gauge or two that way I know that the wire can handle the load without issues. Then I fuse with a fuse that is under a 75 percent load rating from blowing. So if you got a 23 amp draw , 30 amp fuse , 15 amp draw , 20 , 10 amp draw 15 , 5 amp draw 7.5 or 10. If 14 gauge is needed to be in spec , I run 12. If 16 is needed , I run 14. I fuse and run wire for each light back to a sub panel that way the wire can be smaller gauge and each circuit is isolated to each light. It may be overkill , but I would rather be safe than to have an insurance company ask me why I ran all the accessory lighting if I did not know what I was doing and how they are not going to give me a check for 40 grand for a New Bronco that I still owe 50 on that's sitting in the driveway burnt to the frame.

 

[Arrowbear Rider]

Thanks for the info, I had a HF meter that wasn't user friendly and after my buddie with a lot more knowledge than me told me to chuck it I did. Thanks for the link to purchase the amp meter. It's in my cart.

you use the harness built in by ford , and they have lets say 16 gauge wire.

How can we connect to Ford's 16 gauge with 14 or 12 gauge, wouldn't that make Ford's wiring the weak point?

If 14 gauge is needed to be in spec , I run 12. If 16 is needed , I run 14. I fuse and run wire for each light back to a sub panel that way the wire can be smaller gauge and each circuit is isolated to each light.

I have three pairs of CAFOPAR 3" cube lights 40w each, that I am mounting in my mod bumper as my fog lights. Using your numbers, those 240w total should/could draw 20amps. (60w = 5amps) = (240 w = 20amps), would this be correct?

How should I splice the three sets (1 set per pair of lights) of 16 gauge and join them together to one switch? Or two if I with below. Since our choices are (1) 30 amp, (1) 15 amp, (4) 10 amps, that would mean I need the 30 amp for all six lights and the gauge from splicing three sets would have to be 10 gauge (per chart) 15 feet, even though that will be foot or less?

That would not be the best use of my 30 amp switch. I could split off to a 15 amp for two pairs of lights and one 10 amp switches for the other pair. I would have to use the 30 amp for the 300w light bar.

To do correctly, which is what I want to do, it looks like I need to use the 30 amp for light bar, the 15 amp for two pairs of 40 w amber lights, one 10 amp for the other pair in the bumper, maybe put the 4"Nilights if they fit with the amber lights. Then one each, 10 amps for the 8 pc rock lights and another for the 40w ditch lights, 60 if the Nilights.

That's 3 of the 10 amp and the two larger amps switches. One space left.

 

[jharrell3623]

I would wait till I actually saw the load amperage with the meter, before I decided wwhat lights belong on what circuits . Using the factory harness with the factory relay from nilight is safest. Then the aux wire from Ford just becomes a trigger and would not have a load on it. Only on the other side of the relay towards the lights would have the load and if nilight did it right the gauge going to the light should handle the load.

 

[jharrell3623]

Oh and I would test the lights with and without the harness they gave you. Essentially if you use each harness for each pair. You would use the harness as is up to the relay. Then after that you could combine whatever hots you want to control together , then bypass the switch they give you and hook all those hots to the appropriate ford aux wire. You are just removing the switch they give you is all. However from the light to the relay , use what they give ya.

 

[Neigh]

Any problems with the Nilight's wire harness? The one I got is 16 gauge to connect the two ditch lights, which I realized are 4" wide, 60w and the 12" bar is suppose to be 300w. The harness has a 15 amp fuse & 16 gauge says 13 amps, I was going to use a 10 amp aux switch.

I have the six 40w amber lights for total 240w. Which switch do I need to use?

These are all LEDs and am I correct that the wattage claimed is a estimate of what the equivalent of LEDS?

I strongly suspect those wattages are "incandescent light output equivalent watts" or some other such nonsense. I'd suggest you get an ammeter involved and test them to see exactly what they're using. You'll likely be shocked by how little power they actually use.

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