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TR2/3/3A TR3A Horn Wiring Problem

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Tinkerman

Tinkerman

Darth Vader
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I am having a bad time trying to get my head wrapped around the horn wiring on my 1960 post 60,000 TR and would appreciate some simplification on what I'm supposed to be doing. Please ignore any over simplification or bone head comments I might make concerning the problem.
WHAT I SEE:
two horns one right and one left, from the front of the car. Each has two female bayonet terminals on it. I have two long brown/green wires coming from the left and right wiring harness. I have 2 short brown/black wires coming from the right and left wiring harness. I have one brown/black wire coming from the steering column harness.

HOW DOES IT ALL GO TOGETHER?
My wiring diagram shows it all but I'm just too dense today (or dumb) to get it altogether in my head.

Your help would be greatly appreciated.
Tinkerman
 
Well, first you seem to be missing the short (6 or 8") NB (brown/black) wires that run from one of the terminals inside the horn to a bullet sleeve nearby.

On the driver's side, there should be a 4-way sleeve that connects the NB wire from the horn together with the NB from the steering column and the other NB from the main harness. On the other side, just a 2-way sleeve connects the horn NB to the main harness NB. The NB wire in the harness just runs from side to side, so the net effect is to connect one terminal of each horn to the button in the control head.

The two brown/green (NG) wires should connect to the other terminal inside each horn. I kind of like being able to disconnect them without removing the horn cover, so I've modified my horns with short sections of NG wire as well; but the factory did not do it that way.

The NG wires in the harness run to the fuse block, and are hot all the time. You might want to pull the horn fuse out while making connections if you don't already have the battery disconnected.

In operation, both horns get 12v from the horn fuse all the time. When you push the horn button, it grounds the NB wires and (hopefully) both horns sound.
 
The brown/green is power from the fuse box. This wire powers the horn, which is always powered. It goes to one of the female bullets in the horn. From the other female bullet catch comes the wire that connects to the ground circuit (the brown/black wires). On the left side, connect the ground wire out of the horn, the brown black out of the main harness, and the smaller gauge brown black from the control head all together using a double female bullet connector. Then push the button.
Bob
 
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