Is there a 12v constant hot wire wire near the spare tire?

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I'm looking to connect a blue wire from my brake controller to a constant hot wire near the spare tire. Is there such a wire available?
 
I'm installing a Redarc. I already have the Red 30 amp 12 awg wire going to the battery. I don't want to run the full length
of the vehicle for the blue wire which is 12 awg and doesn't need to be fused.

View attachment 3888917
 
What does the blue wire do?
These might help you

20250224_102627.jpg
 
I don't want to run the full length
of the vehicle for the blue wire which is 12 awg and doesn't need to be fused.

View attachment 3888917
Uh, any wire has to be fused, especially one not factory routed and running the length of the vehicle. It's not just about the load it's expected to pull under normal conditions, it's to prevent a fire in the event of a short due to chafing or other things
 
Uh, any wire has to be fused, especially one not factory routed and running the length of the vehicle. It's not just about the load it's expected to pull under normal conditions, it's to prevent a fire in the event of a short due to chafing or other things
To be safe, you are correct, it should be fused, but if I follow the wiring diagram as per Redarc, it doesn't have to be fused.
Redarc wiring diagram.jpeg


I'm still hoping someone could answer the question, "is there a constant 12v wire near the spare tire:?
 
Um, the blue wire is what you’re referring to? The one going TO the trailer brakes? That is going to be a home run from the RedArc to whatever plug you put on the rear of the truck… You’ll have to run it.
 
I should be more precise about what I am trying to accomplish. I am installing a brake controller under the dash, and I am converting a 4 pin to a 7 pin trailer harness. The blue wire is coming from the Redarc all the way back to the brake controller output of the 7 pin, the 7 pin also needs a 12 constant. Rather then running the 12 v constant from the battery up front, is there a 12v constant near the spare tire to connect to the 7 pin? The arrow wire is what I'm looking for near the spare tire.

Screenshot 2025-04-21 at 3.41.34 PM.jpg
 
for that run a separate fused wire.
the trailer plug is accessible by any undesireable when the vehicle is left parked and can be easily tampered with. I have mine wired separetely with a auto reset circuit breaker for that wire / pin
 
To be safe, you are correct, it should be fused, but if I follow the wiring diagram as per Redarc, it doesn't have to be fused.
View attachment 3889628

I'm still hoping someone could answer the question, "is there a constant 12v wire near the spare tire:?
There isn't such a wire, and if there was, it almost certainly wouldn't be sized or fused adequately for a trailer.
But again, if you are running a wire to the battery, it must be fused "to be safe" (that's the whole pointof a fuse, right?) It doesn't matter if the diagram shows it or not. If you end up tapping into a constant hot somewhere in the vehicle and it's got adequate fuse protection for your needs already, that qualifies.

and all this is beside the point because the blue shouldn't be connected to constant hot anyway. If anything you could technically be able to tap into your 25A controller power wire to get your constant 12v, but it's better to just take the effort and make another (fused!) Home run from the 7 pin connector to the battery
 
So i could be wrong, But the blue wire I believe is just the trigger and is not big enough to carry the brake load. The last trailer controller i had the black wire was the big boy that carried the load. Of course my memory might not be correct so validate of course.
 
I should be more precise about what I am trying to accomplish. I am installing a brake controller under the dash, and I am converting a 4 pin to a 7 pin trailer harness. The blue wire is coming from the Redarc all the way back to the brake controller output of the 7 pin, the 7 pin also needs a 12 constant. Rather then running the 12 v constant from the battery up front, is there a 12v constant near the spare tire to connect to the 7 pin? The arrow wire is what I'm looking for near the spare tire.

View attachment 3889639
There likely is a constant 12v wire available at the rear of the 80. Probably on the taillight harnesses. I don’t have an EWD handy to find the wire. I would not get your 7 pin Black power source from tapping an existing fused small gauge circuit though.

Run 10awg duplex from the 7 pin, along the frame DS, to engine bay. One wire is for the 7 pin Black one for 7 pin Blue. Black goes to battery + with a breaker. Run the Blue wire and Black wire from the Tow Pro thru the firewall. Crimp Blue on to the other duplex wire (the one your crimped onto 7 pin Blue. Black Redarc wire goes to battery + with a fuse or breaker (30a). Secure and protect wires under the vehicle. This eliminates you running wires thru the interior.

Finish with under dash local body ground (Redarc white) and brake tap (redarc Red). Just my suggestion. I install these on various vehicles.
 
@Shoredreamer this was very helpful thank you very much. This was the information I was looking for. Would you tie wrap the protected wires on the top side of the frame? Is there anyway to run those two wires inside the frame rail?
 
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