Most OEM horns ground through the bracket that bolts to the frame of the car. Assuming that the green wire is the one that is switched and that you plan to bolt the horn to the frame you probably don't need the the black. But if the grn and blk are together you could always put a loop connector on the blk and put it under the mounting bolt to insure a good ground connection.

 

I've only done one RF harness build, but IIRC, the green goes to the horns (and they are indeed grounded through the bracket) and the black ground wire grounds the relay to activate the horns, thus it must go to the dash to your switch/button.

Mark

 

So what your saying is the RF harness black wire needs to be grounded (to the mounting bracket like Dave M said) to complete the circuit for the relay to work? Then the green to the wire coming from the horn?

 

Ok, I'm not too familiar with the RF harness but if those 2 wires are in fact coming from a horn relay that is part of the harness system then what Mark said is how it should be put together. The black wire being the ground lead for the relay would go to one side of your horn button then a wire to chassis ground from the other side of the switch/button.
Looks like if you hooked it up the way I originally suggested the horn would never shut off. Sorry about that.

 

Dave is correct in his assumption of my previous post. The black wire goes to your dash and whatever button, switch, etc. you wish to use to honk at people... :evil:

Of course this also depends upon where these wires are in the harness. The black wire should be going towards your dash wires, but if it goes towards the "front of car" wires then it could be a true ground wire. Look at the wiring diagram in the RF manual that came with the harness, it'll explain it.

Mark

 

Sorry to disagree with you guys but the green and black wires go to the horns. The FFR supplied horns use both wires. The dash harness has a brown wire which is what goes to the horn button and the other side is grounded. This is also verified by looking at the wiring diagram at the Ron Francis website.

http://www.ronfrancis.com/images/FFR06-INST.pdf

 

Thanks for clarifying Jorge. Like I said, only done one RF harness, which is why I also asked in my second post where the wires are going and that it could be a true ground...

Thanks for posting the true wiring color codes and routing...
Mark

 

So I need to just hook up the green wire to the only wire coming off the horn and the ground wire goes in between the chassis and horn bracket to make a ground.

Thanks for the help...

Ryan

 

Is Ron Francis jacked up or is it me?

On both my horn and fan relays it appears the pins 85 and 86 are and backwards. Both are activated by their switch providing ground, yes? The brown horn wire should go to the button to be grounded when you press. If so it should be on pin 85, right? Mine is on 86. My horn sounds constantly if both the green and black wires are connected at the horns.

likewise, the fan thermo switch, the green wire, should get its ground through the thermostatic switch and should be on 85. It was also on 86.

Do I just swap the pins? I tried that with the horn, and it all just sounds constantly. Wtf am I missing?

 

Anyone?

So close to getting on the road I can almost taste it!

 

Joe,
85 is the plus side of the coil, 86 is the ground side.

Horn Relay - Red on 85, Brown on 86
The red wire on 85 is +12V (hot when key is on). The brown wire goes to the switch, the other side of the switch is connected to ground. When you press the button it completes the circuit from the relay coil to ground, energizing the relay (and the horn).

Fan Relay - Orange on 85, Green on 86
This is setup to allow you to either 1) use a switch or 2) use a thermostat.

If using the switch you ground the green sending unit wire and use a switch to connect the brown gauge feed wire (+12V when key is on) to the orange wire through a switch. When you flip the switch it sends 12V to the relay coil to energize it.

If you are using the thermostat you connect the green wire to the thermostat, and connect the orange wire directly to the brown gauge feed wire (+12V) at the dash. The coil then always has +12V when the key is on, and when the thermostat activates it completes the circuit through the coil to ground to energize the relay.

Hope this helps.
Dennis

 

Your directions match ron Francis... but every diagram I've pulled up online has 85 as the ground, not 86.

when I hook them up per the RF directions, both are running constantly... the switches have no effect.

 

You know, I have never had those terminal numbers memorized, but you are right. 86 is generally shown as the positive.

The Ron Francis harness definitely has them the other way.
I just did a little test with the relay from my RF harness, and they will switch with either polarity applied. According to the tyco cut sheet, they don't have a protective diode, they have a resistor - so that makes sense.

I have some Cole Hersee relays that have the snubber diode around the coil, and the polarity does matter on those. I just hooked one up and verified it won't work the other way.

Having said that, I have my RF horn and fan hooked up as described above, and it works as expected. Not sure why yours would be staying on.

Only concern I have is that I have to make sure I don't interchange a relay with a diode into the RF fuse panel. I might just see if I can push those two pins out of the fuse panel and swap them.

You should give RF a call and ask them why they chose to do it that way...

Dennis

 

It is definitely odd. I was able to swap the pins on both. Horn still has same issue, so I think it's getting a ground elsewhere. Or I need to take the button apart and see if that's messed up. I'll be able to test the fan after I hook the dash back up.