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Horn wiring

Grey owl

Contributor
Sr. Member
Joined
Nov 19, 2024
Messages
395
Why is horn wiring such a mystery. I added a tilt sterring column horn switch and custom steering wheel. The horn has never worked. Infact on my 69 it is the only electrical component that wont work. What is the secret ???. i can make it work with a simple push button switch, but not with the steering wheel button. Does anyone have a simple solution to this mystery.
 

Jdgephar

Bronco Guru
Joined
Sep 25, 2012
Messages
1,517
More information needed. Early Bronco's didn't have any tilt columns. What tilt column are you using? Does your Bronco have the original wiring, or a replacement harness? You also mention a custom steering wheel. You will need the correct adapter plate inside so that the "clock spring" works correctly to complete the circuit (whether that's switching ground or 12V is TBD based on the previous questions).
 

Steve83

Bronco Guru
Joined
Jul 16, 2003
Messages
9,359
Loc.
Memphis, TN, USA, Earth, Milky Way
The secret is all your truck's details. ;) We aren't there looking at it, so you have to tell us EVERYTHING about it every time you ask for technical help with it. Especially all its modifications, damage, & repairs, but also each component (since so many have likely been changed over the decades) and its maintenance history. It's best to put ALL of that in your signature so you don't have to re-type it ever time, and we can find it easily.

But the factory horn circuit was very simple: constant power on a Yellow wire to the switch going out on a Blue/Y wire to the horn which is grounded to the core support.
 
OP
OP
Grey owl

Grey owl

Contributor
Sr. Member
Joined
Nov 19, 2024
Messages
395
More information needed. Early Bronco's didn't have any tilt columns. What tilt column are you using? Does your Bronco have the original wiring, or a replacement harness? You also mention a custom steering wheel. You will need the correct adapter plate inside so that the "clock spring" works correctly to complete the circuit (whether that's switching ground or 12V is TBD based on the previous questions).
It has the original 1969 harness, the column has GM wiring, that has been adapted to work with the ford harness. The signal lights, brake lights etc were all easy and work just fine. There is a single wire coming through column and another short one on the shaft flange. The one coming up the colum does not have power i believe its a ground. The short one is definitely a ground.
 

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
You will need to convert your horn circuit to work with a relay, like the GM based column is expecting.
As Steve said, the original ’69 setup was one power wire IN, and one power wire OUT.
Your new column has one wire in, that grounds to the column when you hit the button.

Connect a 30 or 40 amp 4-pin relay in the circuit.
Pin 30 needs a wire from the battery.
Pin 87 goes to the horn.
Pin 86 gets 12v. Can use the old horn wire from the Bronco’s harness, or just jumper it to Pin 30.
Pin 85 runs up to the single horn wire in the column and grounds when you hit the horn button.
You can add new wire for some of these functions, or utilize existing ones when you figure out where you want the relay.

It’s been almost 40 years since I did this on my ’71, so can’t remember exactly how I routed things, but I think I mounted the relay over by the battery (Edit: scratch that. Probably by the horn to take advantage of the original wires), and pretty sure I only added one new wire.
But my situation was different, in that I used the stock column. Same concept, different wire routing and connections.
Even bought a special tool to poke a hole in each of the rubber firewall grommets to run a wire under the dash from the battery side over to the horn side. Didn’t like the idea of the wire just hanging out on the firewall.
In hindsight I could have run it through the hidden channel under the core support.
You’ll figure out what is best for your setup.
 
Last edited:

DirtDonk

Contributor
Bronco Guru
Joined
Nov 3, 2003
Messages
51,618
The great thing about converting to a relay, is you can now use bigger, more powerful horns. Even more than one.
More power to the horn(s) and longer life out of the horn contacts.
 
OP
OP
Grey owl

Grey owl

Contributor
Sr. Member
Joined
Nov 19, 2024
Messages
395
You will need to convert your horn circuit to work with a relay, like the GM based column is expecting.
As Steve said, the original ’69 setup was one power wire IN, and one power wire OUT.
Your new column has one wire in, that grounds to the column when you hit the button.

Connect a 30 or 40 amp 4-pin relay in the circuit.
Pin 30 needs a wire from the battery.
Pin 87 goes to the horn.
Pin 86 gets 12v. Can use the old horn wire from the Bronco’s harness, or just jumper it to Pin 30.
Pin 85 runs up to the single horn wire in the column and grounds when you hit the horn button.
You can add new wire for some of these functions, or utilize existing ones when you figure out where you want the relay.

It’s been almost 40 years since I did this on my ’71, so can’t remember exactly how I routed things, but I think I mounted the relay over by the battery (Edit: scratch that. Probably by the horn to take advantage of the original wires), and pretty sure I only added one new wire.
But my situation was different, in that I used the stock column. Same concept, different wire routing and connections.
Even bought a special tool to poke a hole in each of the rubber firewall grommets to run a wire under the dash from the battery side over to the horn side. Didn’t like the idea of the wire just hanging out on the firewall.
In hindsight I could have run it through the hidden channel under the core support.
You’ll figure out what is best for your setup.
Thank you i appreciate the help.
 
OP
OP
Grey owl

Grey owl

Contributor
Sr. Member
Joined
Nov 19, 2024
Messages
395
You will need to convert your horn circuit to work with a relay, like the GM based column is expecting.
As Steve said, the original ’69 setup was one power wire IN, and one power wire OUT.
Your new column has one wire in, that grounds to the column when you hit the button.

Connect a 30 or 40 amp 4-pin relay in the circuit.
Pin 30 needs a wire from the battery.
Pin 87 goes to the horn.
Pin 86 gets 12v. Can use the old horn wire from the Bronco’s harness, or just jumper it to Pin 30.
Pin 85 runs up to the single horn wire in the column and grounds when you hit the horn button.
You can add new wire for some of these functions, or utilize existing ones when you figure out where you want the relay.

It’s been almost 40 years since I did this on my ’71, so can’t remember exactly how I routed things, but I think I mounted the relay over by the battery (Edit: scratch that. Probably by the horn to take advantage of the original wires), and pretty sure I only added one new wire.
But my situation was different, in that I used the stock column. Same concept, different wire routing and connections.
Even bought a special tool to poke a hole in each of the rubber firewall grommets to run a wire under the dash from the battery side over to the horn side. Didn’t like the idea of the wire just hanging out on the firewall.
In hindsight I could have run it through the hidden channel under the core support.
You’ll figure out what is best for your setup
Thanks with this i can get this done, i appreciate your help.
 
OP
OP
Grey owl

Grey owl

Contributor
Sr. Member
Joined
Nov 19, 2024
Messages
395
Made a 4 wire pig tail with relay, now just have to tie it into harness.
20260218_123535.jpg
 
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