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+12V Horn Wire Color

Bruzilla

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Anyone know what color the +12V horn wire under the hood is? Or, which wire from the bulkhead connector goes to the horn for a 74 Roadrunner?
 
According to my 74 (Dodge) book it's terminal 12 of the bulkhead connector

It's a poor diagram, but facing the firewall connector, appears to be bottom terminal of third column from the left

They indeed show a dk green/ red going back to the horn relay
 
So, why does the horn use a relay instead of a direct 12VDC draw?
 
Because it's a LOOOOONNNNNGGGGGG ways from the horns to the horn button, and horns draw a LOT of current. There WERE cars (some European) which switched horns directly with no relay.

You must understand that building a heavy duty horn button that can carry all that current is no small task. For one thing that round thing you call the steering wheel TURNS, and so the horn switch must have some from of slip ring and brush to carry the "juice." A heavy duty one would wear out that much faster.

So................we use relays..................
 
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