Does anyone have a tutorial video or photos for the aux switch wire locations for 2025 Bronco Sport

[Ziggydog]

Perhaps that table has a typo for the 30A circuit wire size and possibly also for the 3 10A circuits

table says “Generative summary”, is this table in the owners manual or in official
Ford documentation?

It's from the manual. Check it out for yourself.

Sponsored

 

[Dude]

It's from the manual. Check it out for yourself.

It’s ok … I had 2nd thoughts and updated my post to remove the info you quoted

 

[Ziggydog]

It's from the manual. Check it out for yourself.

I'd love to be wrong, but all of the wires on mine seem to be the same wire guage...

 

[Ziggydog]

It’s ok … I had 2nd thoughts and updated my post to remove the info you quoted

What are you saying? Are you in agreement, or saying that I'm wrong. I don't think there is any dispute that the wire guage is not rated for more than 5A, when in a harness. The switches are rated at 10A to 30A, while being wired with 5A wire. You're good with that?

 

[jkernitzki]

OP posted the schematic in post #14 of this thread. It shows correctly sized relays for each switch. Only switch to relay is 22AWG.

 

[Ziggydog]

What are you saying? Are you in agreement, or saying that I'm wrong. I don't think there is any dispute that the wire guage is not rated for more than 5A, when in a harness. The switches are rated at 10A to 30A, while being wired with 5A wire. You're good with that?

Personally, I think that is wrong, and if my company had done that, they would have been sued into the dark age.

 

[Ziggydog]

maybe this is Ford’s reasoning to label Aux 1 and Aux 2-4 as they did:

Unfortunately no way to confirm the following is directly applicable to the 2025 Bronco Sport Aux switches

1. All 4 Aux Wires Are Signal Wires

• Their only job is to pass a 12V logic-level signal when a switch is pressed.
• This signal is used to energize a relay coil — which draws maybe 100–200 mA, not 10–30A.

2. The “30A” Rating Refers to the Underhood Circuit

• In the fuse panel, Ford provides a 30A fuse & relay position for AUX 1.
• If you run new 10 or 12 AWG wiring from that fuse location to your accessory, you can safely draw 30A — but you must bypass the 0.35 mm² wire.
• Ford assumes the installer understands the need to route heavier wire for high-current applications

Yeah, instead of just telling customer that it's not a real 30A circuit, they play bullshit. I get it

 

[Ziggydog]

Bottom line, people that actually own these... don't hook up anything to the auxiliary switches without a relay. The wires to the switches are only rated for 5A!!

 

[jkernitzki]

Ford’s been putting upfitter switches in their vehicles for a good decade or more. This isn’t their first rodeo wiring these appropriately. So, to summarize:

Relays already there.

Little wires switch to relay.

Big wires relay to landing from factory.

Hook up lights up to rated amperage.

All good.

 

[TheX]

Ford’s been putting upfitter switches in their vehicles for a good decade or more. This isn’t their first rodeo wiring these appropriately. So, to summarize:

Relays already there.

Little wires switch to relay.

Big wires relay to landing from factory.

Hook up lights up to rated amperage.

All good.

^^This^^

 

[jonnyb]

As I awaited the delivery of my Bronco, which is going to spend a bunch of time driving on back roads with an overpopulation of deer, I've been researching how the Aux switches work. So thanks everyone for their input on this thread.

Now that I have the vehicle I can see the accessory wire that is accessible by the BJB (which I think is actually switch B -- the errors in the Ford documentation don't help here!). See photo below. According to the last couple of posts, this is the "thick" wire coming out of the relay, and you should just be able to wire your 10 amp or less accessory directly to it. The problem is that it is not very thick (my hands are small for scale). Definitely 22 AWG. Most Ford products use a 16 AWG or larger wire for this application, which would handle the 10 amp (but not the 30). With 22 AWG I believe you would want to keep the draw well under 5 amps (more like 3 max really). I haven't checked the supposed 30 amp connection, but am not hopeful it is any better. It seems that if you really want to use the upfitter wires for anything more than novelty items or small pod lights, you are going to need to add a second relay and use the upfitter wire just as a signal wire (as Dude above suggested). So basically everyone that has commented recently is right, even when they seemed to be contradictory

In the Bronco Sport article (https://thebronconation.com/news/bronco-sport-sasquatch-auxiliary-switches-how-to-use-t.21841/) they mention that they used this strategy -- wired their novelty horn directly, but added relays for their lights. A little disappointing that Ford downgraded the Bronco Sport wiring from 16 AWG to 22 AWG and therefore made additional relays much more necessary than they should be with the in-built relays, but at least we don't have to mess around installing switches in the cabin.

At least that's how I've put this (and a bunch of other posts on the Big Bronco forum) all together. Would be delighted if I was wrong and the "thick" wire was something else. Next up I need to see if the revised fog light position (which has gone pretty much unmentioned) affects the installation of Baja Designs replacement pods. If anyone has experience there I would love to hear it before I open things up.

 

[Ziggydog]

Is there supplied

maybe this is Ford’s reasoning to label Aux 1 and Aux 2-4 as they did:

Unfortunately no way to confirm the following is directly applicable to the 2025 Bronco Sport Aux switches

1. All 4 Aux Wires Are Signal Wires

• Their only job is to pass a 12V logic-level signal when a switch is pressed.
• This signal is used to energize a relay coil — which draws maybe 100–200 mA, not 10–30A.

2. The “30A” Rating Refers to the Underhood Circuit

• In the fuse panel, Ford provides a 30A fuse & relay position for AUX 1.
• If you run new 10 or 12 AWG wiring from that fuse location to your accessory, you can safely draw 30A — but you must bypass the 0.35 mm² wire.
• Ford assumes the installer understands the need to route heavier wire for high-current applications

Is there a supplied relay for the Aux 1 circuit? I can't find it.... Thanks!

 

[Dude]

… Now that I have the vehicle I can see the accessory wire that is accessible by the BJB (which I think is actually switch B -- the errors in the Ford documentation don't help here!)
… The problem is that it is not very thick (my hands are small for scale). Definitely 22 AWG. … I haven't checked the supposed 30 amp connection, but am not hopeful it is any better.

The issue was the 2025 owners manual lists the wire size and the Aux circuit Amp ratings but fails to mention anything about relays (assuming relays actually are installed by the factory for specific 2025 Bronco Sports)

Owners Manual info posted by @ELCouz:
https://www.broncosportforum.com/forum/threads/bl-sasquatch-aux-switches-wiring-guide.13923/post-233178

Pic in post #14 posted by ElCouz showing relays and the rated fuses:
https://www.broncosportforum.com/forum/threads/bl-sasquatch-aux-switches-wiring-guide.13923/post-246139

Your pic in your post showing the wire gauge size being small would support what the owners manual states but then pic #14 seems inconsistent with that

You are right that the supplied documentation from Ford is inconsistent with posts in various online articles about actual installs using the Aux switches

 

[ELCouz]

Is there supplied

Is there a supplied relay for the Aux 1 circuit? I can't find it.... Thanks!

They are all under relays with different fuses sizes.

I wired AUX1 and AUX2 so far. I am waiting for my ditch light brackets from @FordBroncoLifts ?

No need to install additional relay IF the load is within spec and the wire is very short.

I did for AUX2 because I installed reverse lights that was close to 100w ...too close from the little 10A rating and I had to run the wires until the back of the BS.

 

[ELCouz]

As I awaited the delivery of my Bronco, which is going to spend a bunch of time driving on back roads with an overpopulation of deer, I've been researching how the Aux switches work. So thanks everyone for their input on this thread.

Now that I have the vehicle I can see the accessory wire that is accessible by the BJB (which I think is actually switch B -- the errors in the Ford documentation don't help here!). See photo below. According to the last couple of posts, this is the "thick" wire coming out of the relay, and you should just be able to wire your 10 amp or less accessory directly to it. The problem is that it is not very thick (my hands are small for scale). Definitely 22 AWG. Most Ford products use a 16 AWG or larger wire for this application, which would handle the 10 amp (but not the 30). With 22 AWG I believe you would want to keep the draw well under 5 amps (more like 3 max really). I haven't checked the supposed 30 amp connection, but am not hopeful it is any better. It seems that if you really want to use the upfitter wires for anything more than novelty items or small pod lights, you are going to need to add a second relay and use the upfitter wire just as a signal wire (as Dude above suggested). So basically everyone that has commented recently is right, even when they seemed to be contradictory

In the Bronco Sport article (https://thebronconation.com/news/bronco-sport-sasquatch-auxiliary-switches-how-to-use-t.21841/) they mention that they used this strategy -- wired their novelty horn directly, but added relays for their lights. A little disappointing that Ford downgraded the Bronco Sport wiring from 16 AWG to 22 AWG and therefore made additional relays much more necessary than they should be with the in-built relays, but at least we don't have to mess around installing switches in the cabin.

At least that's how I've put this (and a bunch of other posts on the Big Bronco forum) all together. Would be delighted if I was wrong and the "thick" wire was something else. Next up I need to see if the revised fog light position (which has gone pretty much unmentioned) affects the installation of Baja Designs replacement pods. If anyone has experience there I would love to hear it before I open things up.

AUX1 (30A) is 18AWG. I've measured. The one you are showing is close to 21AWG. I measured the diameter.

Ford can get away with it because of the short wiring and 105c rated wiring.

AUX1 can go 15-20A continuously if the wire is short, if you need a long run use thicker wire at least to prevent voltage drop. I would go minimum 14 awg.

For ditch light normally around 50-60w each it's fine. But don't go near 10A continuous load, more like 6-7A max!