[LATECH]

How the circuit/relay works:

terminal 1 is power feed.It goes to the coil winding, and both the upper and lower points contact arm.all 3 have 12 v + all the time

terminal 2 is the black wire to ground at the horn button.It is grounded when mashing the horn button

terminal 3 is power to the horns (green)(horns are self grounding)

terminal 4 is to the ignition lock cylinder key- in ignition switch and the door switch in a series circuit configuration. Both switches need to be closed to complete the circuit (allow current to flow)

A dot on the wiring diagram signifies a electrical connection,look at the relay coil . It has a dot on the spot where it touches the upper point/contact arm.The half circle at the lower points contact stand (nail shape thing) signifies a jump of that piece and is not a connection.



To make the horn blow , press the horn button . This completes the circuit from terminal 2 to ground, through the relay coil to the upper contact arm which also has one end of the relay coil winding hooked to it, where the other end of coil winding is hooked to at terminal number 1 (also notice the upper points contact/arm on the same circuit )

This pulls the point contact arm down touching the contact post for terminal 3 (the nail looking thing in the picture ,lower points contact/arm) powering up terminal 3 that feeds the horns. The lower set of points/contact arm assembly is a normally open , meaning they rest in the "Off" position
When they "Close" it completes the circuit and current flows to the horns.

For the key in ignition buzzer, it is as follows the power flows to the relay coil, then to the upper point arm , passes through and on to terminal 4. Then a switch at the key needs to be on (key in ignition closing contacts) and ALSO the door switch needs to on (door open switch grounded) .That activates the circuit.

How does it buzz you ask.?

The power flows in the circuit as long as the upper points contact is touching (circuit on) .That set of points is normally closed, meaning always conducting/turned on. well, when the circuit is active , the relay opens the upper points contact, which de energizes the circuit and the points close, power up the circuit again.It does this real fast, like may times a second,and by doing this it causes the relay to make a buzzing noise.

Hope this helps