Location of SWB horn relay

[304065]

Thanks, I had found that posting, and it helped for sure. But how to solve the 5 pin/4 pin was the question.

OK, moving on, I've got my horn (s) working. I have figured out how to do this and will post for those who come later.

First of all, a basic understanding of what a relay is and how it's wired and labeled. Once I had that down pat, the rest followed. A great video here:

http://www.youtube.com/watch?v=JkG22KgciwY

Thanks to Moss Motors - a supplier of my TR3 stuff for this video. As they noted, the numbering for relays is universal. Sure enough, the new relay has the same numbers.

Then, the final piece - an adapter to connect 2 ground wires (one from each horn) to one spade, and then everything falls into place.

Just wanted to be sure you had seen it. Now look closely at your relay--

upper left is 87. This is a pair of fat red wires, actually the power to the horns from the battery. This is "backwards" by DIN, but it works electrically.

Middle terminal-- 30/51-- you can see that this is a dual contact with a rivet in the center holding a double pin. The power wires to the horns themselves go on this. If you look at L57 (wiring diagram) you can confirm this.

Upper right is 85-- this is relay coil power-- when this contact receives power, the relay coil is energized, pulling in the wiper and making the connection between 87 and 30/51. See the brown with white stripe connected? Well according to DIN-- a brown in our cars is a ground, and brown with a stripe is a modified ground-- like the one from the horn ring, a ground that is interrupted by the switch. Sorta makes sense.

Lower right is 86, according to DIN 72552 this is ground, but here you can see it is a "multiple" from the power to 87. This provides power to the relay coil.

Anyway, you can buy brass fastons that have a double connector on the end, the factory uses them throughout the car-- or you can inexpensively buy a "dual 87" relay. In that case you would connect your black/yellow power wires to the horns to the pair of 87s (like DIN says), put your power on 30 and 86 and your interrupted ground on 85 and call it cool.

Hope this helps!

[luke-44]

OK, thanks. I see I still don't have it right as the center 30/51 is not ground as I said above, but power.

Question: "you can buy brass fastons that have a double connector on the end". Where do I shop for these?

This actually started out as a steering wheel swap over project so now I've confirmed the horn problem was in the relay and not the wheel. So I'm able to move forward on that while I wait for the 2 into 1 connector.

But I will try to save the original piece per SKWIKY67, now that I've got a fix.

[304065]

like so

http://www.digikey.com/product-detai...7CT-ND/2233291


you need the right f type crimper too, knipex 97 21 215 is probably the best/cheapest

http://www.early911sregistry.org/for...-for-reference