Questions on electrical diagram for air horn hookup to RXV

[igotboost]

I bought this air horn about 20 years ago in Japan.
I haven't hooked it up for about 10 years and forgot how I did it.
I will be hooking it up to a Blue Sea 6 Circuit Fuse Box w/ Negative Bus that is connected to a 12V reducer on an electric RXV.

Not sure what the symbol in the red circle means.
Not sure why there's a toggle switch in the blue circle.
Also not sure why I need the switch in the black circle if it's going to be hooked up to the steering wheel horn button.

Can anyone walk me through it?

[tag50]

red circle= OEM horn
blue s/w= compressor on/off
black s/w= OEM/air valve

I added air horns to a 64 Rambler American once. Stopped at a red light. The only other car at the intersection on my right was making a left turn. Half way through his turn I hit the air horns. The look on his face when he thought he was getting creamed by a phantom semi----priceless.


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[igotboost]

So if there's no OEM horn I can just leave that connection out altogether?

For the compressor on/off do I need to install an actual switch there? I don't remember doing that in the past. It always just turned on and off automatically when the tank got low.

Is the switch in the black circle just a relay?

[tag50]

1) Yes, that connection wouldn't apply for you

2) An automatic pressure s/w on the tank or in the tank makes the s/w on the diagram unnecessary (there should be an electrical feed still, just not a separate s/w)

3) The s/w in black would allow you to choose which horn sounds off. Since you don't have OEM horn, that s/w is unnecessary also. Wire the neg. side of the air horn valve straight to the horn button.

PS- The diagram shows a chassis ground (which is a big no-no on electric carts). Make hard wire neg. connections to battery neg.


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