Maybe someone can help me with hookin up my new horn, I thought it was easy but well.. didn't get it. The wiring in my truck is old, it has a voltage regulator so its converted to 12v, someone redid the wiring long ago. The horn looks original big,bulky, sounds like a dying duck. There is only one wire running from the horn to the button. The button has two wires (the one to the horn) the other wire looks like its grounded behind the dash...heres a little diagram of how I was supposed to wire the new horn (followed directions that came with it), and nuthing happened. I tried a few different sources for power and just hooked it up to the positive on the battery terminal..still nothing. Any ideas?
http://img175.imageshack.us/my.php?i...diagram8mn.jpg

 

Joe, When you had the positive hooked directly to the battery, where was the ground hooked up? Try running the ground directly to the battery negative and the postive to the battery positive(make sure your fuse is good) if you have nothing then the horn itself is probably bad.

if the horn works, then I would start looking at your ground circuit

Bobby

 

Thanks for the quick response, I have "figured" out electrical stuff before but it definately is not a strong point. I took the horn button out of the dash and followed the wires. One wire runs out the firewall and went directly into the stock horn, the other wire went up under the dash and is screwed onto a lil box looking thing. I wish I could take a pic but my digital just went out on me. I just bought the horn new, and it came out of the box so I hope its not broken. I will try that tomorrow,I guess that is completing a circut? If I have this right then...from the button one wire goes right to the negative of the battery, the other goes into the negative of the horn. Then from the horn positive it runs to the positive of the battery. The fuse is good, just picked up the parts, wires etc.. tonight.

Thanks again all.

 

Joe,

Horns take a lot of current to operate. That's why modern vehicles use a relay for horns. I recently wired the horn on my 48 using the starter button as the horn button. I use the button to activate the relay which is isolated from ground and the relay activates the horns. You can wire up the horn circuit without one, but it will never work as well as it would with one. You might want to pick up a relay and rewire the horn system. Any 12V relay would work...

Vern

 

Vern is right. The relays work great. Basically, you are putting a big heavy (shorter also) run of wire from the battery to the relay. Then the wire leaves the relay and goes to the horn. The smaller wire that goes to the horn button tells the relay when to close and send power to the horn. Relays are also the answer to your weak headlight problems if you have them. Good luck, Jag

 

1 - Take bobby's suggestion and test the horn (without going through the horn button) at the battery first. This will let you know that the horn works.

2 - Repeat step one but add the horn button to the circuit. This will let you know if you have a problem with the button.

3 - If one and two worked, I would replace or at least clean up the screw you were using for a ground and verify that you have clean metal at the ground source. Also verify that you have a good ground from the battery to the frame and from the engine to the frame. Also, verify that you have a good ground from the cab to the frame. If one and two above worked, I supect you just have a bad ground where the horn was grounded previously.

4 - If one and/or two did not work above, you likeley have a bad component. If it's the horn, chances are the hornm is just bd. It happens. If the button doesn't work, try cleaning things up. These are not very complicated and you should be able to figure out how it works with once you have it apart.

5 - The relays are probably a good idea but I'm not terribly comfortable recommending what type to use. I'm mechanical engineer and my approach to solving electrical issues is to treat them like plumbing/fluid flow problems. It's a crude approach but usually gets things figured out. Get the basics working (horn adnbutoon) then add things (wiring and relays) and get them working, then install and verify it is still working. Hope this was some help.

 

Carl -

Get out of my head!!!! I am also a mechanical engineer. Your description of how you solve electrical problems is so like how I think of them it is truly scary. I thought I was the only one without the electrical chromosome. Seems to be a virus.

 

Randy,

You're not alone. One Important thing to keep in mind when working on electrical systems is to make sure that there are no wires with bare ends pointing down. If that happens then all the juice can run out of the battery and nothing will work. So if you see a bare wire or one that isn't connected to anything, always bend it so it points up

I think its time for a frosty beverage.........

Bobby

 

Thanks, Bobby. I didn't know about the bare wire thingy. Sure makes sense to me, though.....

 

Randy,

One of the reasons I love these old trucks is because nearly everything is mechanical, and therefore simple, right down to the windshield wiper motor. A little lubrication and everything keeps working.

The electrical stuff is all FM (M= magic) to me. My problem solving dissertation above was handed down to me from my father, a NASA-type ME, hence I've always refered to it as the mechanical rocket scientist approach to electrical problem solving. While it's certainly an over-simplified approach, I've always been amazed at how well it works on anything electrical. Houses, boats, cars, etc. Glad to know I'm not the only knucklehead - errr - ME that does this.

 

I will post my findings soon, I have some homework then I'm going to tackle the horn. I looked at it this morning and the wire is grounded/screwed into the back of the wiper switch. On a good note, I have some new wheels 15"front/16"rear coming Thursday, along with front rear sway bars, some new weather stripping, and a handful of other goodies. =)