Hey guys,
I'm thinking about buying a train horn kit for my 2014 F250, but I would like to utilize my upfitters control the comp. and the horns. I would also like use a relay somehow to have both horns sound when the steering wheel is pressed, and with a flip of the upfitter turn the train horn off.
Can anyone help me with a descent description of how I would make this happen. I'm not an electrical genius but with some good spiritual guidance I can handle just about anything.
Thanks in advance for any help or feedback.

 

I have never messed with these horns on a truck like yours, only on a big rig that already has air. Will the compressor have a air tank? If it does, turning the compressor off will not turn the horns off. The compressor's job is to keep the tank full. You could still hook it to a upfitter switch, but it won't keep the horn from blowing.

 

Franklin2, the compressor will have a tank and the horns have a solenoid that I guess could also be powered by an upfitter switch, but I am trying to put in a relay that gets power from the trucks horn that will also power the solenoid too, so that with a flip of an upfitter will sound both horns, but when turned off only the truck horn sounds. I hope that what I am trying to do makes sense. I have seen videos of it but they are not very clear on details.

 

I'd tap into the horn wire out from the steering column just below where the clock spring connector to the chassis wiring is located---this would be the air horn relay/solenoid trigger. From there back to one side of the upfitter switch out the other side to the relay for the solenoid. Power the relay as always hot, use the upfitter switch only to ground the relay coil which in theory would reduce the load on the switch although in this instance the relay coil won't draw too much power. Because power might be more readily accessible under the hood all this might make this a bit easier, not running as much wiring.

Once the relay is hot, upfitter switch to "on" and test relay for proper intended operation. If all okay connect the solenoid and you should have your "traffic mover" ready to annoy the masses.

 

Thanks JWA, thats exactly what I am trying to do. But you make this sound really easy to do. I am definitely not real electrically savy.

 

i tapped into the horn wire coming out of the steering column, and sent it to a single pole double throw relay.


relay is powered by a switch. flip switch on and relay gets energized sending power to the air horn solenoid. flip switch off and relay powers off sending power to electric horn.
compressors get power directly from batteries to relay to compressors energized by another switch.
this way i can turn compressors on/off at will, and switch from electric to air horns at will.

 

tjc transport, so the comp. will go to one upfitter and the train horn solenoid will to the relay which gets power from the truck horn which will go to the other upfitter backto the relay? Is that about right? Like I said "Im not an electrical wizard". LOL/

Just dont want to screw this up. But want to do it myself.

 

not quite.
my system uses two relays, and 2 upfitter switches.
relay#1 can be a single pole single throw relay, and is wired like this:
compressors are battery to circuit breaker, then to 30 on relay, then from 87 on relay to compressor.
85 on relay goes to the upfitter switch, then to a switched power source in the fuse box, 86 on the relay goes to ground.

relay #2 is the single pole double throw and gets wired like this:
for the horns, i cut the horn wire in the column and put it to 30 on relay. the other end of the wire from the column goes to 87 A which is usually connected when the relay is powered off. 87 goes to the air horn solenoid.
86 goes to ground, 85 goes to an upfitter, then to a switched power source in the fusebox.
this way when the key is turned off, the compressors shut off also so you do not come out to dead batteries in the morning, and the horn reverts to electric horn with key off.

 

Thanks Tom.
I'm beginning to think that maybe someone else should do this.
Are you up for the challenge?LOL

 

Simplest way would be to power the compressor with one of the upfitter switches. I believe most of these switches are powered on/off by the keyswitch. I would not use this to "control" the horn blowing, just as a power source for the compressor. If you wanted to not use the horns for a long period of time, you could turn the compressor switch off, but normally I would just leave it on and let it pump up by itself.

Ok that's the compressor power. Next is the control. There are several ways to do this, I believe reading between lines you would like the simplest easiest way. One question I have; Look at the wiring for the air horn solenoid. Does grounding the wire to the solenoid activate the air horns? Or does it need power to activate the air horns?

 

almost all horn solenoids are 12 volt to engage Dave.

 

Dave, you are correct. I am looking for the simplest way of going about this.
I have already figured that the compressor will be toggled on/off with the #2 upfitter. Now I am trying to figure out how to use the #3 upfitter to power the train horn solenoid on/off. When the train horn is toggled on I would like both the truck and train horn to sound, but when uppfitter is of only the truck horn will sound. I know there will be the use of a relay and power coming from the truck horn and all that, but its the actual wiring and such that I'm not to familiar with.

 

The air horn solenoid needs power. The truck's steering wheel most likely grounds out to make the truck's horns sound. So I think the easiest way will be to tie into the truck's horns out near the horns themselves. Use the horn power to power the air horn solenoid.

That will make both horns sound at the same time.

The upfitter switches supply power. So to use the upfitter switch for control of another circuit, you will need a relay. Let the relay interrupt power from the horns to the air horn solenoid.

I will see if I can make up a drawing, anyone else who wants to can certainly contribute with a drawing or if they have a even simpler way. The upfitter switches only wired to supply power are making this more difficult that it has to be, but it might be easiest for him to use.

 

Franklin2. Thats what im looking to do. I'd really appreciate a diagram of some of sort.

 

Here's a diagram to get the jist. Get a relay and see if you can figure out how it works and what the terminals do. We can help you with that.