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Aux switch relay/fuse question.

pablo94sc

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After looking at the relays in the junction box for the upfitter circuits, 1-6 appear to use the same relay part #. Do y'all think we could simply swap fuses around, say aux 3 with 5, to upgrade one of the rear circuits to 25A? This assumes the wiring is the correct guage, which I'm not 100%.

All this came about because I disliked using a 15A circuit for maybe 3A of chase lights, and thought maybe aux 1 and 3 could be swapped. Thoughts?

Relays:
Ford Ranger Aux switch relay/fuse question. 20260513_105626


Ford Ranger Aux switch relay/fuse question. Screenshot_20260503_125805_Edg
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CaptAngry

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The fuses are paired to the wiring gauge. So those lower current circuits have thinner gauge
 

MasterCylinder

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After looking at the relays in the junction box for the upfitter circuits, 1-6 appear to use the same relay part #. Do y'all think we could simply swap fuses around, say aux 3 with 5, to upgrade one of the rear circuits to 25A? This assumes the wiring is the correct guage, which I'm not 100%.

All this came about because I disliked using a 15A circuit for maybe 3A of chase lights, and thought maybe aux 1 and 3 could be swapped. Thoughts?

Relays:
20260513_105626.webp


Screenshot_20260503_125805_Edge.webp
The 15 amp fuse are on approximately 16 Gauge US equivalent wire. The wire can safely handle about a constant 13 amp load and a surge of around 18 amps but will blow the fuse. The 25 amp wire is approximately 14 gauge equivalent and can handle a constant 20-22 amp load and a surge of around 28amps. That's why the fuse ratings are used accordingly to the wiring capabilities. There are variables such as wire length that also plays into an overall situation but stick to the fuses rating on that particular circuit to avoid issues! The fuse size does not determine the amount of current flowing in a circuit at any given time, if the load does not require it. It protects the wiring from too much current flow. Hope this helps! :like:
 
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pablo94sc

pablo94sc

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Well, y'all have answered my question. Guess without repinning the junction box, it's not going to happen the way I want. Next best option, splice into the aux 3 circuit near the junction box with a T-splice, which worked perfectly and, once the electrical tape is removed, can easily be disconnected if I need to run something off aux 3 in the rear.

I'm now debating chase lights on aux 1 and a long wire run to the back of the truck, or aux 4. Thoughts?

Thanks again!
 

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jordantii

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Well, y'all have answered my question. Guess without repinning the junction box, it's not going to happen the way I want. Next best option, splice into the aux 3 circuit near the junction box with a T-splice, which worked perfectly and, once the electrical tape is removed, can easily be disconnected if I need to run something off aux 3 in the rear.

I'm now debating chase lights on aux 1 and a long wire run to the back of the truck, or aux 4. Thoughts?

Thanks again!
My chase lights are on Aux 3. A Pillars on 1-2 and 5. The long run is not worth it IMO.
 
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pablo94sc

pablo94sc

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My chase lights are on Aux 3. A Pillars on 1-2 and 5. The long run is not worth it IMO.
Given the cost of wiring, probably not. I'll save aux 1 for rock lights or something. Thanks.
 

Harlequin_Forest

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That was such a slap in the face cost cutting measure to leave the pins how they were for the ROW Raptors. I was also considering repinning the wires but still haven't gotten around to it
 

jordantii

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My chase lights are on Aux 3. A Pillars on 1-2 and 5.
Given the cost of wiring, probably not. I'll save aux 1 for rock lights or something. Thanks.
You could always get Nacho lights. They are direct to battery so you don't have to worry about load. The triggers are all low voltage for the lights and you can run 3 scenes. On Aux 1 I have full power running at 80 watts for each light. But since they are direct to the battery for power the load is nothing for the triggers. So 5a on Aux 1 is perfectly fine even for 80/160 watts.

For chase lights, Nacho Nano's just use Aux 3/4. The Nano's are not direct to battery for power.
 
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pablo94sc

pablo94sc

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Just a quick update and FYI: both of my rear circuits used a solid brown wire for 12v, but had the correct wiring (black/green, black/gray) for the aux 3 & 4 grounds. Of course I cut the one for aux 3 first... 🙄
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