Horn Problems

[Nut Tree]

OK, guys I need help from some of the amazingly talented people that frequent this forum. I just started the redo on my 92 f350 - the truck in my signature. I am fairly mechanical, and I can paint and sort of weld, but I am dumber than a post when it comes to electrical. So here we go. My factory horns don't work so I ordered a couple of WOLO Big Bad Max horns to replace the OE units. AFTER the horns arrived, I decided to test the originals. I ran a hot wire from the battery terminal to the horn and it went off. So, then I knew the horns were good and my problem must be the switch. I removed the cover on the steering wheel and the wires weren't connected to the switch plate. I connected the wires and got nothing so I removed the horn switch (copper plates with foam in between) and tested for continuity and the meter sounded when they were pressed together so I knew the switch was good. Next I tested the ends of the wires for power and there was none, so I unplugged them from a connector buried in the steering wheel and tested them for continuity and they were good. Finally, I tested the connector in the wheel for power (there are 3 little prongs) and nothing was hot. Now what?????? I don't want to hook up an separate button for the horns and don't how to trace from the connector back to wherever. I am eager to learn and not afraid to get dirty, but just don't have the knowledge/expertise. Please help.

 

[79jasper]

Check the horn fuse. Lol
And there's also a relay.


Sent from my iPhone using Tapatalk

 

[franklin2]

I don't know about 92 models, but on the older models you only got a horn relay if you had cruise. The trucks without cruise had a simple switch like he described, power in, power out to the horn, no relay. The ones with cruise the switch pad grounded the wire from the relay to the column.

 

[theguruat12]

I'm not sure if you already did this (can't quite tell from your description) but if you can test for continuity between whatever the switch is wired between (be that ground and one wire out, or two wires out from the switch). This will tell you if the copper brushes are making good contact. (Brushes are the little spring-loaded post thingies that allow the wheel to rotate while keeping an electrical contact).

If that checks good (or if it already checked good) then test for continuity between the horn plug and the wires on the switch. This will test the wire from the switch to the horn to see if it's cut/broken.

If those check out, then the issue is with power supply to the switch (be it a cut wire, a fuse, or a relay). IF it works the same as my 85, which is what franklin described about the switch grounding the horn relay to turn it on, then once you test the switch in the column/wiring in the column and make sure it's continuous all the way to the relay, you should check for power on both sides of the relay. If neither is hot, then you have an issue again with the supply circuit. If ONE is hot, and when you press the switch, the other one goes hot, then it's a problem with the wiring between the relay and the horn unit. If you press the switch and it DOES NOT go hot, then bad relay.

 

[Nut Tree]

Ok, where do I find the relay? Also, no fuse positions in the dash fuse box are listed as being for the horn - first thing I checked Lastly, I do not have cruise control if this helps.

 

[theguruat12]

I guarantee the horn has a fuse, even if it's not in the interior panel. Somebody else with an OBS truck will have to confirm where it is though.

 

[79jasper]

Under the hood.


Sent from my iPhone using Tapatalk

 

[franklin2]

In 1989, the power for the horn comes from the 30amp fuse that feeds the cigarette lighter. That is the yellow/lightblue wire. It's not too clear on the 89 diagrams if you should have a horn relay or not, but that may not help you on the 92. If they kept this circuit the same, you can check your cigarette light fuse and see if it's good.

 

[Nut Tree]

I know the powerpoint works, but never tried the cig lighter in the ashtray. I'll go out and test it now and I will also look under the hood for anything labeled "horn".

 

[Nut Tree]

Ok, after the shift tube problem, I am back to the horn problem. Definitely not getting power to the column. There is no "horn" fuse in the interior fuse box and the box under the hood has no labels at all. I did have someone tell me their relay was behind the dash next to the glove box so I'm going to go out and remove the glove box now and look. Anyone have any ideas where the horn relay/fuse is on a 1992? Seems like this would be a common thing.

 

[gandalf]

Ok, after the shift tube problem, I am back to the horn problem. Definitely not getting power to the column. There is no "horn" fuse in the interior fuse box and the box under the hood has no labels at all. I did have someone tell me their relay was behind the dash next to the glove box so I'm going to go out and remove the glove box now and look. Anyone have any ideas where the horn relay/fuse is on a 1992? Seems like this would be a common thing.

Of course there is a fuse for the horn. Ford simply did not do a very good job of labeling it. On my '92 the horn fuse is under the hood, in the power distribution box. That's located on the driver's side fender. The fuse is a 20 amp fuse, left hand (left being toward the front of the truck), third position from the fender.

That fuse also controls the cruise control, I believe. You said you do not have cruise? I'm not sure whether that would affect the horn fuse.

The ultimate solution, of course, is to start pulling and testing each and every fuse with a multimeter. Pull only one at a time, and replace it before pulling the nest.

 

[79jasper]

I'll get a pic.

You must be registered for see images attach

Horn/Cc fuse on left.
Horn only relay on the right.
Need a owners manual?


Sent from my iPhone using Tapatalk

 

[icanfixall]

Thanks for the very nice clear pic. Nothing nicer than a clear pic of what your talking about.

 

[Nut Tree]

Wow, you guys are amazing!!!!! OK, I'll go out and look now, as my patience are too frayed to deal with my "no Park" issue right now. Thank you again.

 

[Nut Tree]

OK, now I'm at a loss. The fuse shows 12v in and 12v out with full continuity. I pulled the relay and tested it according to the included link and it tested good as well.
No what?

http://easyautodiagnostics.com/ford_relay_tests/relay_bench_test_2.php