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HELP!! Upfitter switch wire capacity- Fire Danger??

CalvinT

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SPVPARTS

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HELP!! 24 WT- using a 10A upfitter switch (#4, Fuze #63) with 2x Rigid Industries 6" 360 Pro Amber Spot Lights. Draws 5.1 AMPS per light (10.2A/pair) according to spec. Are equipped with a backlight on a separate power source. After multiple uses, Main lights do not illuminate when switch is activated. Backlight remains on when Bronco is powered.

My stock upfitter setup is as follows-
Switch #1 (30A)- 2x Rigid Industries 6" 360 Drive Lights (10.2A)- Bumper Upper
Switch #2 (15A)- 2x Rigid Industries 6" 360 Spot Lights (10.2A)- Bumper Upper
Switch #3 (10A)- 2x Rigid Industries 4" 360 Spot (4A)- Bumper Lower
Switch #4 (10A)- 2x Rigid Industries 6" 360 Pro Spot (10.2A)- Ditch Lights
Switch #5 (10A)- 2x Baja Designs S1 Backup (2.9A)- Backup/Reverse
Switch #6 (10A)- 2x Rigid Industries 4" 360 Pro SAE Fog (5.6A)- Bumper/Lower

Using SPV harnesses to connect all lights to upfitter switches at firewall. Have NOT checked fuze yet. Questions for the team-

1- What is the amp rating for the stock upfitter wire?
2- Is there any fire danger adding an @SPVPARTS Harness RELAY/FUSE Add on Adapter to my existing setup (stock upfitter wire (10A Swtich) to SPV Harness)?
3- What is risk with putting a 12A fuze in the 10A slot for the stock switch?
4- Am I better off putting four 6" on the 30A Switch (#1) and avoid any potential issues?

Please and thank you for any feedback.

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20250121_153459_resized.webp
Hey there.

So I just saw this. You can always feel free to reach out any time you want to us for help. 317/934/6778 or info @spvparts.com

(I have worked direct with Ford and Roush Performance over a 20 year period. So I have a lot of experience to offer)

So, on changing fuse sizes in the existing fuse panels. That's a big NO NO.
For a couple reasons. While it seems like its just an amp or two... If there ever were an issue, warranty or insurance wise. (Mostly warranty) You run the risk of them denying the claim for negligence.

This seems a little ironic though, given the fact (and someone pointed it out here I think too) that on the Aux 1 switch which is 30 amps. They are using 16 gauge wire.
In fact all the Aux wires are 16 gauge I believe and so are all the pass through wires.
In the BEST situation, 16 gauge is typically rated at 15 amps max with a SHORT distance. Add in the pass through lengths and its a bad idea for much more if any. That's why they get so hot.
So its one thing if FORD made that mistake. However, you can bet if you change something higher they would be first to point the finger at you. Whoever missed that though at Ford and put a 30 amp on 16 gauge should be reprimanded. Super Duty trucks have 30 amp circuits with 10 gauge wire.

Also, the safe rule of thumb not to burn a fuse is 20% less than the fuse rating. So on 10 amps, 8 amp draw. However, in many cases you can push that as high as 10% (which is 90% of the fuse rating)

So, if you want to be SAFE. If you are exceeding the amp rating of a switch. It isn't a big deal. Just add a relay adapter. We came out with a MINI relay adapter and fuse that is a quick plug in for just these situations.
It plugs into any of the harnesses and any switch. It would use les than an amp on any switch as it gets its power from the battery and the MINI ones have a 25 amp fuse. The full size have a 40 amp fuse.
Technically the PINS in the connectors max at 20 amps so to use more than that you would just want to crimp the 2 connections together. Which is RARELY even needed. In your case especially you should be able to simply plug in a mini relay and the 1 or 2 you may need will take up little space compared to anew box.

Here is a video to explain them and a link.

Please feel free to reach back out. We cant tell who you are by just the forum name, but if you reach out we can always go over everything and help with any questions or concerns.

John



https://www.specialtyperformancepar...1&_sid=bf6cebff4&_ss=r&variant=46584359518440
 

Tonka Bronka

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Turns out they make exactly what I had in mind! 6 relay controlled circuits. Mount this near the upfitter wires in the engine compartment, splice the leads and job done!

91ENYDvrGmL.webp
That looks nice. Looking at the length of the positive lead, it would need to be next to the battery, which is fine. Source please. Ford did an ok job with extra positive studs at the battery, just not enough. One more accessory and I'll need this. Thanks.
 

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Hey there.

So I just saw this. You can always feel free to reach out any time you want to us for help. 317/934/6778 or info @spvparts.com

(I have worked direct with Ford and Roush Performance over a 20 year period. So I have a lot of experience to offer)

So, on changing fuse sizes in the existing fuse panels. That's a big NO NO.
For a couple reasons. While it seems like its just an amp or two... If there ever were an issue, warranty or insurance wise. (Mostly warranty) You run the risk of them denying the claim for negligence.

This seems a little ironic though, given the fact (and someone pointed it out here I think too) that on the Aux 1 switch which is 30 amps. They are using 16 gauge wire.
In fact all the Aux wires are 16 gauge I believe and so are all the pass through wires.
In the BEST situation, 16 gauge is typically rated at 15 amps max with a SHORT distance. Add in the pass through lengths and its a bad idea for much more if any. That's why they get so hot.
So its one thing if FORD made that mistake. However, you can bet if you change something higher they would be first to point the finger at you. Whoever missed that though at Ford and put a 30 amp on 16 gauge should be reprimanded. Super Duty trucks have 30 amp circuits with 10 gauge wire.

Also, the safe rule of thumb not to burn a fuse is 20% less than the fuse rating. So on 10 amps, 8 amp draw. However, in many cases you can push that as high as 10% (which is 90% of the fuse rating)

So, if you want to be SAFE. If you are exceeding the amp rating of a switch. It isn't a big deal. Just add a relay adapter. We came out with a MINI relay adapter and fuse that is a quick plug in for just these situations.
It plugs into any of the harnesses and any switch. It would use les than an amp on any switch as it gets its power from the battery and the MINI ones have a 25 amp fuse. The full size have a 40 amp fuse.
Technically the PINS in the connectors max at 20 amps so to use more than that you would just want to crimp the 2 connections together. Which is RARELY even needed. In your case especially you should be able to simply plug in a mini relay and the 1 or 2 you may need will take up little space compared to anew box.

Here is a video to explain them and a link.

Please feel free to reach back out. We cant tell who you are by just the forum name, but if you reach out we can always go over everything and help with any questions or concerns.

John



https://www.specialtyperformancepar...1&_sid=bf6cebff4&_ss=r&variant=46584359518440
Hey John,

Seems I already had an SPV Mini Relay I had previously purchased. Installed it Tuesday night and everything is working as advertised again. The SPV Mini Relay was so easy to install, especially since everything was already plumbed with SPV harnesses and connectors.

Is Sydney still working at SPV?

Matt
 

SPVPARTS

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Hey John,

Seems I already had an SPV Mini Relay I had previously purchased. Installed it Tuesday night and everything is working as advertised again. The SPV Mini Relay was so easy to install, especially since everything was already plumbed with SPV harnesses and connectors.

Is Sydney still working at SPV?

Matt
Hey, it's my favorite "Rando!"

Your Grace, The Dutchess of Unwatched Videos, is indeed still here.

Hope you're doing well, buddy! I greatly miss our email threads! 🙃

-Sidney
 

swamp2

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@EOS Would your SAPS unit help @SeabearDivers ?

@swamp2 in case you don't get the notification for the EOS account.
Thanks. The SAPS is designed for always on (unswitched) fused power. I don't think most lights are installed that way.

Only loosely related, but it does look like the upfitter stitches can be always hot or only on with ignition.
 
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CalvinT

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Only loosely related but it does look like the upfitter stitches can be always hot or only on with ignition.
Follow the threads where people retrofitted the stock upfitter switches. A couple of people modified them so they were always hot. It's possible to modify them so that SW5-6 are always hot and the rest on with ignition or vice versa.

Just change the wiring for pins 1 or 9 on CBP02. CBP02 is one of the connectors at the upfitter switches.
 

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Turns out they make exactly what I had in mind! 6 relay controlled circuits. Mount this near the upfitter wires in the engine compartment, splice the leads and job done!

91ENYDvrGmL.webp
Can you post a link to this relay box? Is this a good option in all cases as long as wire gauging and fusing supports the current draw?
 

mdainsd

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There are many types on the web, just search "Automotive relay box".

Here is the type I am currently going to use. I like the screw terminal strips rather than splicing on longer wires to reach.

https://www.ebay.com/itm/317073935577
 

bastardsonofelvis

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I don't know why Ford used such ghetto wiring for the upfitters. I used relays where I needed to (after blowing a couple fuses) and now I'm thinking about only using the upfitters for switches and using relays even on my smaller lights. That relay box someone linked to is pretty sweet. Rewiring might be a winter project.
 

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There are many types on the web, just search "Automotive relay box".

Here is the type I am currently going to use. I like the screw terminal strips rather than splicing on longer wires to reach.

https://www.ebay.com/itm/317073935577
I am generally skeptical of screws to pinch wires to secure them for a reliable electrical connection. These can and likely will loosen in a vibration and thermally cycling environment. The raw leads on the "bad" or perhaps merely inconvenient design Ard superior with a proper crimp and crimp tool.

The unwanted potential side effects of a loose screw terminal connection include: poor device performance, high resistance, overheating, corrosion and fire.
 

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I don't know why Ford used such ghetto wiring for the upfitters. I used relays where I needed to (after blowing a couple fuses) and now I'm thinking about only using the upfitters for switches and using relays even on my smaller lights. That relay box someone linked to is pretty sweet. Rewiring might be a winter project.
Don't repeat or add to any mistakes Ford made. If your not an expert in this area, I'm happy to share my SAPS Instructions, whether you buy one or not. It has, more or less, a crash course in choosing tools and materials to do a very high quality wiring job.
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