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I need some horn help...the last thing on this project is just not right.

C

Coupe

Member
OK, so my 65 has had pretty much everything changed or refinished. I replaced the turn signal switch when I redid the interior this spring and now the car is done right....not so fast.

My horn makes a weak "Grunt" when I push the horn button, so I figured it was a bad ground on the horns so I clean off some paint and made sure the star washers had a good bite and double check and its not the problem. If I send a power jumper from the battery to one of the horns they both honk fine, so its not a ground.

OK, its gotta be my old original plug that the new column harness plugs into right? Well, if I short between the two corner wires (Yellow & Yellow/green) on the original plug (Car side) the horns honk fine.

When I check continuity on the column side plug when I push the horn button it shows contact closure.

I was really scratching my head here so I plugged everything back together under the dash and pulled the wheel back off (Lecarra) and put a jumper across the two spring posts and all I got was a "Grunt" (With some heat). The terminals are new, they look fine and the springs allow them to slide... but I cannot get them to act right? Its like they are not allowing enough current through. I cleaned em with lacquer thinner and then a scotch-bright with no change.

What is going on? I am going to try and remove the turn signal switch and flip it over tomorrow and see what gives, but I am really curious as to what would cause this to act this way?
 
Are you sure the horns are the same wiring type as the column...one type completes the circuit, the other type provides a ground to complete it. Burnt some wiring that way once....
 
Wait what? From what I see the 12 volt (yellow wire) sends voltage to the horn button and the outgoing wire then sends that voltage to the horns that are grounded at where they connect to the cars body.

Its pretty much a restored car as far as wiring and parts go.
 
You have a voltage drop in the column.

I would wire a relay in the yellow with green side to give the horns a full 12 volts. You could do this right under the column tapping the yellow wire as the 12v source for the relay as long as you have a full 12v coming in on that wire. The relay needs at least 8v to trigger.
 
Hmm. I may need to do a relay then.

Its weird because now if I use a wrench across the two spring post terminals it honks, but if I test across those same terminals with a test wire with clips on the end it just grunts (And the clips get hot)? And the horn button still grunts. Its like the smaller wires cant pass the current.


Any specific relay P/N or instructions on wiring that would be appreciated.
 
It sounds to me like a crappy crimp connector somewhere within the turn signal switch, probably at the wheel contacts.
 
I do suspect the wire that is soldered to the copper horn ring inside the lecarra hub, it looks sketchy and could be adding resistance, but that does not explain how without the wheel on the car the test wire will not juice it enough but a wrench will.

I guess it could be a crimp down where I installed the new terminals for the old plug when I installed the new column harness.

I am going to go disconnect one of the horns and see if it will honk then with the horn button,.I restored those things and I guess its possible they are drawing too much and I read where an adjustment could allow then to draw less current.
 
Well, FWIW with one horn hooked up it works fine. Either one will honk, but not both together. The main underhood harness is new up to the firewall plug but the harness on the drivers side apron is original and looks good. I double checked the firewall plug for that side and all looks good.

The only thing that looks iffy are the plugs that go onto the horns themselves, they fit a bit on the sloppy side, but clearly they work, just one at a time.
 
Your gonna need a relay. I'd use the ground to control the relay like this. Run the 87 wire to both horns.
 
"67 evil eleanor" said:
Your gonna need a relay. I'd use the ground to control the relay like this. Run the 87 wire to both horns.
Click to expand...

Thanks. I guess Ill do that after the holiday.
 
That wiring diagram don't look right. With 85 wired to 30 the trigger is hot all the time, 86 is getting a feedback ground through the left horn closing the relay and sounding the right horn all the time.

30 should go to +B, 85 should go to ground, 86 should be the trigger from the horn button and 87 should go to both horns.
 
Your using the ground as the control wire in the first drawing. Both circuits are open until you hit the button. Hit the button ground the coil and the contacts close and the horn blows. This one below shows the (+) as the control wire. It's six of one and half dozen of the other.
 
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