horn wiring

Reply Subscribe

Thread Tools

Search this Thread

Mar 22, 2010 | 09:57 AM

Poison Oil Racing

Thread Starter

Posting Guru

Joined: Nov 2007

Posts: 1,305

Likes: 2

From: Montgomery, IL

horn wiring

On my '76 I only have one horn but I think there should be two. How are they wired together?
The horn I have has a blade connector on it and I have that wired up just fine but there is also a machine screw sticking out of the top of the horn, Any idea what that is for?

Mark

Mar 22, 2010 | 10:14 AM

Shane in WI

Senior User

Joined: Jun 2009

Posts: 329

Likes: 1

I think the machine screw is for tuning or adjustment of the horn. There is only one wire to the horn. It's grounded by the mounting bolt. I believe I have seen 2 horns that have a jumper wire between them.

Mar 22, 2010 | 10:50 AM

Poison Oil Racing

Thread Starter

Posting Guru

Joined: Nov 2007

Posts: 1,305

Likes: 2

From: Montgomery, IL

So are most of our trucks only using one horn? Mine works fine but the Haynes wiring diagram shows 2 horns,

Mar 22, 2010 | 10:53 AM

Furyus1

Postmaster

Joined: Dec 2008

Posts: 3,940

Likes: 8

From: Southern Oregon Coast

Mine has 2 horns - I assume they're wired in parallel. One of my future projects is to wire in relays and run a set of Wolo's...

Mar 22, 2010 | 10:25 PM

fmc400

MSEE

Joined: Apr 2004

Posts: 10,386

Likes: 35

From: Austin, TX

The dual horns use a high-note horn and a low-note horn wired in parallel. A single horn would have been standard. I'm pretty sure a '76 has a horn relay too.

Mar 23, 2010 | 07:26 AM

Poison Oil Racing

Thread Starter

Posting Guru

Joined: Nov 2007

Posts: 1,305

Likes: 2

From: Montgomery, IL

Quote:

I'm pretty sure a '76 has a horn relay too.

Yes it does, but the weird thing is that the relay doesn't actually go to the horn! One wire goes to the starter solenoid and the other wire goes into a plug which then goes to the back of the alternator.
Very strange.
I just ran a new horn button to my horn to get it all to work properly.

Mar 23, 2010 | 01:54 PM

ChaseTruck754

Lead Driver

Joined: May 2007

Posts: 6,993

Likes: 15

From: Costa Mesa, CA

If your question hasn't been answered completely enough - yes there is just a "jumper wire" from one horn to the next when 2 horns were on the truck, and yes it seems 1 horn was a little more common than 2.