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Old 03-04-2007, 07:59 PM   #1
Kantosensei
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Horn not working

When I depress my horn button I get a clicking noise under the dash, but the horn doesn't blow. Is there a simple test to check the horn or is there a relay that could be bad. My horn was working, then I changed my entire under dash wiring harness, I thought i had checked everything after changing it and am pretty sure it was everything was working. I had two horns under the hood and two horn wires (green). One of the wires has a double terminal and is not hot. The other is a single terminal and is hot (12 volts when button is depressed). I know for sure that only one horn has ever worked. Is it possible that the horn is not grounded? I have scuffed the paint to bare metal. Is it possible that the horn would just die?? I am totally baffled and need to go to inspection. Any ideas would be greatly appreciated. Thanks David
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Old 03-04-2007, 08:53 PM   #2
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Re: Horn not working

Start looking at grounds. If you changed dash wiring is possible that just by moving stuff around, under steering wheel cap isn't making contact.
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Old 03-04-2007, 09:41 PM   #3
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Re: Horn not working

Hook up a test light at horn wire. If it kights when horn button is pushedb, horn is bad.
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Old 03-04-2007, 11:02 PM   #4
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Re: Horn not working

Horn is good. I ran a wire from the horn to the battery and it works. When the horn buton is depressed I get a clicking noise in what appears to be a relay next to the fuse block. I swapped that out and still get the clicking noise. The plug for the relay has a red, green and black wire. I hooked the test light to the red and grounded it and it is hot. THe green did nothing, I;m uncertain what it does. I have had the steering colum apart and checked to make sure all contacts are clean etc. If any one has any other ideas on what and how to check I will be greatly appreciative, my sanity will be greatly appreciative. Thanks again David
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Old 03-05-2007, 01:10 AM   #5
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Re: Horn not working

If you could have seen what I pullled out of the underdash wiring harness you would be completely amazed that the truck would even start much less have lights, radio etc. and also that it didn't catch fire. Since I changed that, I am guessing that it was not compatible with the birds nest that I just pulled out from under the hood. I just changed the undrhood harness with a clean, uncut harness that I purchased from a board member and now my horn works. I thank you for your ideas.
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Old 03-05-2007, 12:42 PM   #6
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Re: Horn not working

Here is how your horn works:
1--Red wire is the power wire to relay-hot all the time. -checks ok
2--green wire runs from relay to horn-here is where you need to check to see if the green wire has a circuit between relay and horn. (this sounds like your problem)
3--black wire is a ground wire-it run from relay to horn button-when horn is pressed it grounds this wire makeing the relay close to send power from red wire out thru green wire to horn. Black wire is ok.
4--To test run a wire from green wire on relay out to horn. If it works your green wire is broken somewhere.
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Old 03-05-2007, 06:31 PM   #7
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Re: Horn not working

I'll have to remember that one, very good info 66
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Old 03-05-2007, 07:47 PM   #8
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Re: Horn not working

Thank You! That is good info, especially for people like me who have no sense of electrical components. I knew it had to be something like that after I realized that I did have power to the red wire. I should have taken pictures of the mess that I had. The previous owner had used fourteen different color of wires and had things jumpered from one thing to another. It would have taken an electrical guru to figure it all out or someone with a lot of patience. Thanks again for the info.
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Old 03-05-2007, 09:44 PM   #9
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Re: Horn not working

Remind me to post this in the FAQ.
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Old 03-06-2007, 01:09 AM   #10
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Re: Horn not working

Glad to help. GM has used the same color code for the major circuits since I stated fooling with chevys in 1956. (I traded in a 1950 2dr Ford sedan for my 1st new car--a 1956 Bel-Air 2dr HT-265 4Bar-3 on the tree) I still own it.
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Old 03-06-2007, 01:55 AM   #11
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Re: Horn not working

Quote:
Originally Posted by jhow66 View Post
1956 Bel-Air 2dr HT-265 4Bar-3 on the tree) I still own it.
I hate you. ......I bought one in 1980 for $100, put a battery in and drove it for a couple of years. Sold it for $200 to buy a '73 El Camino......actually, I still kick myself for selling that car.
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Old 03-06-2007, 02:21 AM   #12
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Re: Horn not working

Quote:
Originally Posted by FLEET72 View Post
I hate you. ......I bought one in 1980 for $100, put a battery in and drove it for a couple of years. Sold it for $200 to buy a '73 El Camino......actually, I still kick myself for selling that car.
Here is what it looks like now: (sorry kant' not trying to hijack your thread-if you need more help on your wiring, let me know.)
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