I have searched many old threads in this forum and I have not found the answers to my problems. My horn started acting up (it would sound when I crossed a bridge or hit a small bump) a while back. That night the horn was blowing contiuosly. I went out and slapped the horn button a few times and it stopped. That was the last time the horn worked. I thought it might be the horn button. I removed the bolts holding the air-bag from the steering wheel, unplugged the air-bag and the horn. Checked the horn plug for voltage and had 12 volts there. Pulled the horn button/contact. Checked it for ohms at 200K at the wires, it showed a short circuit.

The Ford place wants $337.00 for the "horn repair kit." . I ran the horn wires out the back of the steering wheel, bought an old fashioned horn button. Wired it up and nothing happens. What is wrong with my thinking? Shouldn't it be a make or break circuit? If the horn relay is bad.....I cannot locate it. The manual doesn't tell you where it is, if it is part of another relay or what. Someone told me the horn relay was on the back of the fuse panel. If it is , I certainly can't see it. If it is, would I have to remove the fuse panel. That would seem a little bit ignorant.

I really need some wise help with this one. Thanks.

 

have you tested the horn itself?

 

There's a '05 horn wiring diagram and some other info in this thread:
https://www.ford-trucks.com/forums/8...use-short.html

 

Not a Ford but that was the problem on my Harley. Don't assume anything. It will bite you.

 

whats the old saying about K.I.S.S

 

Pull the two-wire plug to the horn. Check for power and ground there with the horn button depressed. If both are present, replace the horn. If not, do your tracing to see where the circuit is open. And yes, I agree with the K.I.S.S rule.

 

I had simmiliar, pushed horn sounded like a dead duck and blew fuse. replace fuse did it agin. Reached up with long screw driver while pulling on horn plug wires, cut off the plug, pulled wires back and mounted new horn by the vacume pump. Worked great for a few days THEN at 4AM it goes off in the driveway for no reason at all HOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOOk I poped the hood disconnected the horn. Now I just yell out the damn window.

 

OK guys...I'm not as sharp at this troubleshooting as I used to be. I guess I have been retired too long.

It turns out that I was wrong about the horn button/contact. I soldered the wires back together on it, reinstalled it and it is working like it is supposed to. 15 amp fuse is good (#37). Took me forever to first locate the horns and then remove the passenger side fender liner. I did not have voltage at the horn wiring with the horn button pressed. I could hear a clicking at the fuse panel when I depressed the horn button. I took the wires loose that go up to the steering column. I tested the dark blue wire and again heard the clicking at the fuse panel. In my limited knowledge, it sounds like the switch to the horn relay is stuck. I removed the fuse panel and found what I believe is the horn relay on the backside of the panel. Naturally, it is not removable. Does this mean that I am supposed to buy a new fuse panel to get a new horn relay.

Please remember all of your advice about k.i.s.s. Don't assume I know what you are talking about. Please fully explain everything to me. I confess my ignorance. Thanks for your help.

 

kiss = keep it simple.
the horn relay is in fact part of the sjb (or fuse panel)
dont really see them fail. replaced lots of horns though.

 

I am a former Marine and an old man, I very well know what KISS means.

I wish you had been so much more specific in your answer. I didn't gain any knowledge from it. It would have been better to just ignore my post.

You never mentioned what the clicking sound I heard at the horn relay could be. Stuck switch or not? You did not address what possible reason there might have been that I didn't have voltage at the wiring at the horns. I am not a trained Ford mechanic and I have desperately been asking for good advice. Your answer solved nothing for me. For instance, if, in your opinion, you don't really see the horn relay fail - you never told me how I might determine if it is good. If you have replaced a lot of horns, is there a way for me to test my horns to see if they are good or not, or, do I just simply play the parts swapping game until I stumble upon the correct solution.

That is what I hate about forums like this. You guys with the knowledge grace us ignorant people who are trying to work on their trucks (not because I'm cheap, but because I am on a limited budget) with two or three words and expect us to have all of your understanding. It will never happen. Are you actually trying to help people or just trying to run you post count up?

I still need help if there is anyone else out there who doesn't mind taking a little time to explain these things to me.

 

I agree with Moe about KISS. And I won't bother explaining what the acronym stands for either since you already know. As far as explaining what's involved with your horn issue goes, it all comes back to the basics of what every electrical component requires to function, POWER AND GROUND. This particular circuit is about as simple as it gets, since it literally only involves the horn switch (a. k. a. air bag assembly), air bag sliding contact, fuse #37 in the central junction box along with the accompanying relay and then finally the horn itself. Just by virtue of the fact that the horn relay clicks tells me there is nothing wrong with that part of the circuit. That leaves only the black wire and the yellow with light green stripe coloured wire. To check for ground, simply connect the alligator clip end of a test light to the passenger side battery positive terminal, and probe the black wire. If it lights up, the ground side of the circuit is intact. Now to check for power, switch the alligator clip end of the test light to the negative terminal of the battery. Have an assistant press and hold the horn button while you probe the yellow with light green stripe coloured wire. If it lights up, the horn is faulty. If it doesn't, then you need to trace that wire for an open circuit between the horn connector and the connector to the central junction box (a. k. a. the interior fuse panel). It doesn't get any more complicated than that, unless you want it to. And yes, I agree with Moe, I have only ever had to replace the horn itself for this concern on the ones that've darkened my doorstep.

 

m-chan 68,

Thank you so much for your reply. While this may be as basic as it gets, it's overwhelming when you don't know what to do. You have given me hope as well as all the knowledge I need to troubleshoot this circuit. I cannot express how much I appreciate your help. I am off to work on my truck with confidence. I'll let you know later what happened.

Charles Capps

 

I don't want to get personal or disrespect you but I must say cheezit is a knowledgable and very helpful contributor to this site. He has talked over my head a few times as well , however, I find your response above offensive, undeserved, and simply in bad form.

 

m-chan 68,

I followed your instructions as you had written them out. It did turn out to be the horns. I have installed new ones and everything is working like it is supposed to. Thanks again for your help.

 

Ok so I have read all these posts hoping to find some answers to my horn issue. Here is my deal..... One day my horn worked fine like it was supposed to, then the next day it didnt work at all. I checked the fuse and saw that it was blown. I replaced the fuse to inly use the horn once before the fuse blew again. Ive checked all the wiring I can see/find and it all checks out. The ground looks like its still grounded tight. I am minutes away from wiring in an electric air horn system for 2 reasons, one the fuse issue and 2, well because the factory horn is week. My wife's honda has a better and louder horn that my truck. Any advise?