Horns not working

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Joined
Dec 28, 2014
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Location
Washington Twp. Mi
My Car
1972 Mach 1 Q Code
Hi all, I am having problems with my horns not working. The hi pitch one doesn’t work at all and the low one just sounds sickly. It barley works at all. I did try to connect the hi one to the low pitch wire, but it still doesn’t make a sound. I still need to try switching the low to the hi wire, to see if those wires are good, but I think the horns are just going bad. 
I have been looking at replacing these, but I cannot find any. I have a 1972 Mach1 with a/c and the only replacements I could find were for cars without air conditioning. Anyone know if they can be fixed or where I can get the right ones? I really need to have a working set, so any help would be appreciated! Thanks 

 
Hi all, I am having problems with my horns not working. The hi pitch one doesn’t work at all and the low one just sounds sickly. It barley works at all. I did try to connect the hi one to the low pitch wire, but it still doesn’t make a sound. I still need to try switching the low to the hi wire, to see if those wires are good, but I think the horns are just going bad. 
I have been looking at replacing these, but I cannot find any. I have a 1972 Mach1 with a/c and the only replacements I could find were for cars without air conditioning. Anyone know if they can be fixed or where I can get the right ones? I really need to have a working set, so any help would be appreciated! Thanks 
Vintage horns take more amps. There is 20A fuse in series. Make sure the wires are not rusted, broke and grounds are good. Maybe horn switch has some higher resistance and causing a voltage dip. Check voltages, etc. Non AC car  horns  should be ok.  Not sure about fixing them. 

 
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Disconnect the factory wire and run a wire from the battery  positive post to the horn.  If the horn works correctly you have a low voltage issue, consider adding a relay.

(insert shameless plug here: )

https://www.rccinnovations.com/index.php?show=menu-relays#horn 

https://www.npdlink.com/product/relay-kit-horn-makes-your-horns-sound-like/195993/200452

If the horns don't work when 'hot wired' check for a good ground. The horns ground through the mounting bracket to the chassis.  Check for paint or corrosion, then retest

The horns tend to get dirt and moisture in them which can build up and clog the horn. Insects also like to nest inside them.

There are some you tube videos showing how to disassemble and clean the horns.

 
Hey thanks for the replies guys! I will do some more investigations and see what I come up with. I did make sure they were grounded good cause I have new paint in engine bay, but I was having this problem before. Thanks again 

 
 I know they are site supporters Jim, have bought from them before. OMS is out of stock and the ones Mike has are cosmetic only. I always look at them first, but thanks anyway! Plus I keep seeing there are different ones for a/c cars vs non a/c. Not really sure if they are though. 

 
Disconnect the factory wire and run a wire from the battery  positive post to the horn.  If the horn works correctly you have a low voltage issue, consider adding a relay.

(insert shameless plug here: )

https://www.rccinnovations.com/index.php?show=menu-relays#horn 

https://www.npdlink.com/product/relay-kit-horn-makes-your-horns-sound-like/195993/200452

If the horns don't work when 'hot wired' check for a good ground. The horns ground through the mounting bracket to the chassis.  Check for paint or corrosion, then retest

The horns tend to get dirt and moisture in them which can build up and clog the horn. Insects also like to nest inside them.

There are some you tube videos showing how to disassemble and clean the horns.
I just went ahead and ordered your relay kit. I’m sure they will work better with the relay anyway once I figure out what exactly is wrong. 

 
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Hello jpax,

As nice as your car is you are probably are trying to stay OE as possible. The rocketman relay kit is a good start. Anything that can take the load off an almost 50 year old wire harness can't hurt. As he also suggested, cleaning years of dirt, moisture, and debris that collected in these horns throats could also be a solution. Finding original production installed horns that are good working or rebuildable cores is becoming hard to come by. The Ford service replacements were universal fit that included a couple of different brackets to fit everything. These cars that have service replacement horns functioned the same, but did not have the exact same appearance as the original horn with the permanent bracket that came on your car. The next choice is nearing the Concours level. There is a company that restores these horns to original specs. Not cheap, but is a choice...https://www.carhornrestoration.com/index.html

I also don't know what vendor is indicating different horns for A/C and non A/C vehicles, but Ford does not have their horns listed as such. The original service part horn coverage goes back to 1956 on the car line and 1964 on light truck. None of them indicate A/C or non A/C applications. 🙂

 
Hello jpax,

As nice as your car is you are probably are trying to stay OE as possible. The rocketman relay kit is a good start. Anything that can take the load off an almost 50 year old wire harness can't hurt. As he also suggested, cleaning years of dirt, moisture, and debris that collected in these horns throats could also be a solution. Finding original production installed horns that are good working or rebuildable cores is becoming hard to come by. The Ford service replacements were universal fit that included a couple of different brackets to fit everything. These cars that have service replacement horns functioned the same, but did not have the exact same appearance as the original horn with the permanent bracket that came on your car. The next choice is nearing the Concours level. There is a company that restores these horns to original specs. Not cheap, but is a choice...https://www.carhornrestoration.com/index.html

I also don't know what vendor is indicating different horns for A/C and non A/C vehicles, but Ford does not have their horns listed as such. The original service part horn coverage goes back to 1956 on the car line and 1964 on light truck. None of them indicate A/C or non A/C applications. 🙂
Secluff, Thanks so much for the link and the great info about the horns! I would like to keep the original horns in working order if possible. I still need to test them to see if they will work like Rocketman suggested. 
 

I didn’t think there would be a difference in a/c vs non a/c cars, cause we know how cheap ford could be. So why would they make different horns for the same car, doesn’t make sense. I think I saw that from CJ Pony and NPD. I think one of them listed them as passenger side and drivers side? Just seems like more misinformation about our cars, but you have straightened that out for me, thanks again!!

 
CJ and NPD list the 1967 - 68 horns as fitting our 71-73 cars.

67-8 did have a different horn for cars with A/C

While 67-8 horns look close to our horns, they do not sit in the proper direction, they are turned the wrong way

Manufacturer says to rotate the horn for 71-3 ...  that doesn't work when I tried it.

 
No doubt as to specific horns used on the production line. Was not a problem when the vendor was shipping these horns by the thousands when all the different car and truck lines were in full production. Full frame cars with metal fender aprons, unibody cars with tight under hood areas, and dozens of under hood configurations in car and truck lines made for a lot of creative packaging just for this one part.

But as a service part that would not be economically feasible for Ford to try to stock all the dozens of different configurations used across the corporate production lines with no idea what would sell. No production installed horns were released for service. The service part I previously mentioned goes back to 1956 and continued to be used as a service part until 1983 when an identical appearing horn with two brackets was released with a plastic housing. If you don't want a Wal Mart looking horn under your hood then you need to find OE horn's from a donor 71-73 or have yours repaired/restored.

 
Ok, I just tried the direct wire from the battery to the horns. The hi still doesn’t work but the low one did. I made sure that they were grounded. I’ll check out a rebuild video and see if I can get it working.

 
Mine always seem to fail when I’m at the State safety inspection. Once a fat spider flew out of it. Lol. I’ve found that poor ground has been the biggest issue. Clean the bolt and the area where it bolts to. 

 
543f4fd4cf8ce1e817ab6b829577b3e2.jpg


Easy fix. Bumper sticker LOL

 
Thanks to SteveO_71 for recommending The Horn Works. After testing mine and they were for sure not working, I sent them to The Horn Works to get rebuilt. It took about 3 weeks to get them back, but they showed up yesterday and I installed them today. And guess what? The horns work! Lol. I also got a horn relay kit from Rocketman to go with the newly rebuilt horns.
They sound great and are quite loud. They are supposed to be louder than stock, but I can’t really say for sure since my horns never really worked well since I got the car. But anyway, I am very happy so far. I just need to tidy up some of the wiring and go for a drive. I’m sure it won’t be too long till I get to use them with all the idiot drivers out there! Here’s a couple pics of them after being rebuilt.

31AB2AEE-1B45-4FB9-8917-8C768B4909CB.jpeg

C443A9E6-51D2-4AE7-9876-29A3A1A37789.jpeg

27610C6A-E350-4358-9F5C-9D28CD5400CF.jpeg

 
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