55 Pontiac Wagon Horn relay

[Wagonman]

Can anyone help me with a Horn relay problem. When I put power (12 volts) to the relay it makes contact but I do not get 12 Volts to the H terminal only shows about 1/2 volt. The horns work when I put 12 volts to them but will not work through the relay. I have the original that came on the car and a NOS replacement and both relays act the same. Ignorance is bliss can someone help.

John 55 2562DF 4 door Wagon

[lgorden]

See wiring diagram in Shop Manual (page 12-0) and attached image from the wiring diagram. The H terminal goes to horns. The center terminal is always hot with 12V. The S terminal goes to the horn button. As Jeff says, when you press the horn button, it creates a ground (to the S terminal) which closes the relay and supplies 12 V to the horns.

To check if the relay is working properly, ground the S terminal. If the horns work when you ground the S terminal then you have a problem between the S terminal and the horn button (likely within the horn button). If the horn does not work when you ground the S terminal, then the relay is bad.

[Wagonman]

Thanks guys The problem was the ground.