VCCA Home Forums TECHNICAL - 1945 AND EARLIER 1937-1945 Wiring Harness for Town and Country Horns

To buy a wiring is no option for me, because mine is a right hand drive - talked about this with YZN.
And one Fuse is not very save, so will try do make a complete new, optimized wiring.
Again the question. Is my drawed wiring possible. Why the connection in the middle between second Horn Relais, Light Switch and first Horn Relais?

Link to a bigger Image

That connection in the middle is providing Positive (+6 volts) directly to the horn relay so the horns do not draw power through the Ammeter or Ignition Switch. This prevents damage due to the large current draw by not going through the Ignition or Ammeter.
Just like a modern car, you want the horn to work without the car running as well.
I think this diagram is lacking some connections to the Town an Country Switch as a switch requires at least 2 connections and I suspect would need to be tied to horn ring. Find other wiring diagrams (even close model years) and compare them all so you eliminate any possible printing errors from the day or in being copied.

Andre,

I think the switch grounds to the dash when a selection is made.

Just be clear, Gene, I think you say, and have implied, that there were no trumpet style horns for the 41 and later models. Accordingly, the switch for 41 merely controlled one or the other of the existing horns. Low tone for city and both for country. Is this correct?

Thanks,

Charlie

Thats correct Charlie, look here
http://chevy.oldcarmanualproject.com/accessories/40ca/40ca07.html

Ground to the dash, that was my opinion too

I agree with Tim. The one link missing to me is a wire that connects the Town & Country switch back to the horn button. That wire is needed so the second relay is activated when the horn button is pushed (grounded) and the switch is in the Country position.

Grounding to the dash will make the second horn blow continuously when the switch is in the Country position.

As you can see, only one cable at the Switch..

I would still suggest finding some other diagrams to compare. I think something is missing in the diagram if the T&C switch only connects to one wire/ground as the upper horn is isolated from the horn button.

If you look at the wire coming from the steering column in the diagram, there is something unusual in the schematic. Right above the ammeter there is a thick arch drawn with 3 lines on it. If you go over to the horn nearest the T&C switch, there is a similar thick arch with 3 lines that is not crossing any other wires. It seems to me they were trying to show a crudely drawn connection/selector switch between these two points.

Thanks for the picture of the switch. I agree that it strongly indicates that the switch does ground internally. It would be easy to check that with an ohmmeter.

Given that it does ground internally, I still agree with Tim that there is something missing in the wiring diagram. I cannot understand how the second relay is connected to the horn button.

Will check this on Saturday

@ canadiantim. Unfortunately there are no electrical diagrams with the town and country horn and two relays. The three lines you mean are from the original schematic, I just erased them to have a better overview.

I will show the complete schematic later. Of course it cannot be excluded that I made a mistake when removing and documenting the old wiring harness.

I wonder if Gene has a copy of the original instructions? Can't think of where else we could find a source for the wiring diagram for these.

I just realized I have a set of these to wire up eventually so glad you've posted about this as I'll have to figure out the wiring eventually anyway. You could PM or email me the diagrams if it's too ugly to post.

The schematic in the above link is the easiest way to connect these. Both horns are connected in parallel and only one relay is used. Both horns operate 100% of the time when the horn button is used.

If you want the T&C switch to work: You could simply add a 2nd relay at the 2nd horn that is controlled by the T&C switch.

I'm attaching two pictures. One showing the original wiring schematic and one showing how to add the T&C switch. You could do the same wiring with a small horn on the manifold and then TWO horns added in parallel to the 2nd relay operated by the T&C switch.

EDIT: There is a problem with the detail for the relay wiring but this is a general sketch of how it could be wired. No time to edit right now. How many terminals do your relays have?

Thanks for the schematic. I have three Terminals. 9 to horn and 20(10) to Lightswitch is shure, what i know about the Connections. Only at 30(11) could happen a mistake in my plan for the second horn

Yes Sir! So, no Mistake om 30(11). Tested this with the Multimeter.

Ohoh, but other mistakes in my Plan. What have i drunk that Evening . Now, here is the correct plan for T&C Wiring on 1940. Looks like your drawing canadiantim. My problem was, that I had labeled some cables inside with the same number i used outside, when I disassembled them.

Ray,

Thanks for the information. I'm sure a heap of guys are interested in getting it right.

As for me and the 41, I don't like the switch sitting up there on the dash. It looks just terrible up there. It looks like a dried out chunk of snot or a dead beetle of some kind right out of the deepest part of a jungle somewhere. Does too! On first sight you want to take your hand and flip the thing out the window.

Worst accessory switch ever from Chevrolet. (How's that for not ending a sentence with a preposition?)

Best

Charlie

Hi Andre,

I agree that your wiring should work. I doubt if we will ever know the "real" solution, but yours will work.

Pushing the horn button will create a ground path and activate the first relay. Power will go from the first relay to that one horn and to the second relay. The second relay will activate only if the T&C switch is set to "Country" which will ground that relay.

Another question. How does an 3 Pin Relay works inside? Only know 4 Pin Relays.

In a 3 pin relay there is only one connection that feeds power to both the coil in the relay and the downstream function that it turns on. That is why the one wire that brings power to the relay has to be large enough to carry the amperage for the downstream function such as the horn or lights.

In a 4 pin relay there are actually 2 wires that bring power to the relay. One small wire provides power for the coil in the relay. A larger wire provides power to the contact points within the relay. The coil circuit and the "power" circuit are not connected electrically.

The downstream pins are the same on both relays One completes the circuit to energize the coil and the other sends power to the function.

This also explains why the horn relay on our Chevy's is part of a "grounding" circuit. The wire going to the horn button can be small because the only electrical load on it is the energy to close the coil. That happens when you complete the coil circuit by pushing or "grounding" the horn button.

ok, understand. Like this.

Exactly! Pictures are better than words!

Hope you got the horns to finally make some noise. Sorry I vanished from the thread after getting involved. I ended up with a rash of funerals all a plane ride away so have been preoccupied and funding the airline's projects rather than my own...