The Stovebolt Site Forums The Shop Area The Electrical Bay 1946 Chevy 1/2Ton - Wiring Horn Relay

I'm trying to finish up my wiring project and still have a wire by the dash, but not sure how/where/if it should be connected? It is labeled #13 on my harness and I have three ends with #13. I have a horn relay and it has a wire (#13) that goes to the horn (#13). I have power in and a wire that connects to the horn button. I tested the #13 wire in the dash and it has continuity to both #13 wires in the engine area (relay and horn). My wire harness instructions has them as: 13- Horn Relay to Horn, 14- Power Feed to Horn Relay, 15- Horn Button to Horn Relay. I have those covered, but trying to figure out what this extra #13 wire? I am updating to 12v with alternator.

Possibly for a second horn???

John - Refresh my memory please. Which wiring harness did you get?

Oh boy - 20+ years ago, but I believe I got it from Jim Carter's. It was made for the 12v conversion. Sheet says: 1940-46 Wiring Harness w/Alt EL168.

That extra wire is in the dash area behind the gauges.

In my 6v diagram, it shows a wire from the ammeter to the horn. Would I need that if I'm using a relay?

John - Here's the only thing I could find at the moment for the EL 168 Wiring Harness

I found the EL 168 harnesses listed as being sold by Chev's of the 40's as well as Classic Parts. Doesn't appear to be much help as it only lists one #13 wire. Sorry

Makes me wonder if the harness was designed for use with or without a horn relay?

Yes - I added the horn relay. Not really sure if I need it or not. Something to think about I guess.

Yep - Those are the instructions I have. You can see why I was worried about this part of my project. I was hoping to have step-by-step instructions guiding me through all the wiring, but no so. Good news is I'm almost done with it. Need to get the headlights wired and installed and a couple small clean-up items. I'm feeling good.

Probably wouldn't matter much. The wire probably is a ground to the horn button. Or maybe hot to the horn. Either way, the relay contacts (normally open) would just interrupt the ground for the horn circuit, and the relay coil would get power from a hot source and be grounded on the other side would go the horn button. The relay just takes the load off the horn button contacts. Diagrams available on the web, but most seem to interrupt the power side of the horn circuit. That would be appropriate if the horn is grounded internally, but ours are typically two terminal - hot and ground, with the ground switched.

I tested the horn on a battery and it works, so I installed it on the firewall. I couldn't get it to work with the relay and horn button. I tested the BLACK wire from the relay to the steering column after removing the steering wheel. Nothing, so I cleaned the brass colored ring on the end of the column and now there is continuity - wiring is good. Trying to figure out how the relay should be wired and how it works. This morning I switched the RED and BLACK wires (GREEN stayed in the middle for power) and I can push the horn button and it works. My question about the relay is: Using a test light on the right tab with the BLACK wire, relay clicks and the light is on. When I push the horn button, the test light goes off and the horn sounds. Does all that sound correct? (I added a diagram that Phil (Phak1) posted on another thread a few years ago. He said 6v and 12v are wired the same.)

I’m not much help with relays but checking that you have the rubber piece that goes on the retainer

John: This should help you understand what you are seeing with the test light.

Bill,

I was wondering how the relay worked. Your diagram made it clear!

What "rubber piece" are you talking about??

Update: Did a search and ordered the rubber ring part. I didn't have one.

Thanks Bill. I'm thinking I have this correctly wired now.

Fits on the lip below his finger

I don't remember seeing that rubber bumper when I removed the steering wheel, but that was 20+ years ago. I got one ordered and I'll get it installed. Thanks for the help Ponchogl!

I replaced the rubber bumper today, then the horn button sat a little lower and didn't push in very well. I guess I did have the old rubber bumper, but I thought it was part of the three pronged cast piece. It was hard like plastic. I pry it off and replaced it with the new bumper. Now the horn button works like normal again. Thanks guys!

That’s good to hear. I had to redo my mast bearing under the steering wheel. I had wire drawn through the column but not hooked up and I was reading the other day about the gasket in the hole the wire comes out so I am also happy to see that. I’m hopeful that my horn blows. I will need to test it before moving on with that.