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Old Radio Tech
07-23-2017, 08:14 PM
Which side of the horn gets the voltage, coil side or contact side? Works either way.

Skip Lackie
07-24-2017, 09:04 AM
Probably not gonna be of much help. Both the single and dual horn setups used a horn relay. On the dual horns, the body of the horn is grounded and the single wiring post gets connected to the H terminal of the relay -- but I don't know to which side of the horn that hot wire goes. I seem to remember the single horns have two contacts: aren't they labeled somehow?

rbisacca
07-24-2017, 12:28 PM
R series trucks had a single horn standard and dual horns were an option. The single horn has one contact and the optional 2nd horn has 2 contacts. Studebaker Shop Manual 2R Series Trucks has a wiring diagram on page 61 in the electrical section.

Old Radio Tech
07-25-2017, 01:23 PM
The single horn I have has 2 contacts, one to the horn button and the other to 6vdc. Have not found a horn relay. New wiring harness was installed by a previous owner and all wires are now numbered not lettered and no cross reference. 6vdc appears to be coming from one side of the ammmeter.

Skip Lackie
07-25-2017, 04:26 PM
Shop manual shows a relay was used for both single and dual horns. Wiring diagram shows one contact connected to horn button, the second one to relay/hot, and the horn itself grounded by a third wire. From this I assume the internal horn mechanism is isolated from the horn assembly itself? Anyway, I'd wire it that way and give it a try. If the horn blows constantly, swap the wires on the two contacts.

Lynn
07-25-2017, 10:59 PM
Don't think my 2R16A has a horn relay for the single horn. As for which side gets the 6V, I would have to look. If you are not in a hurry, I will be glad to check it this weekend.

rbisacca
07-26-2017, 12:22 AM
According to parts manual relay was included in optional dual horn kit. Not used with single horn.

Old Radio Tech
07-27-2017, 02:06 PM
The horn mechanism is isolated from the assembly. Haven't found a third wire. Assembly getting it's ground by being bolted to the truck. The mechanism is a normally closed relay with the circuit being completed through the relay contacts. pushing the horn button activates the relay opening the contacts which breaks the circuit closing the contacts and completing the circuit again, so it's a never ending open/close (vibrating) action as long as the horn button is pushed. The horn works whether the voltage is applied to the contacts and the button is applied to the coil or if they are reversed. Trying to figure out which way is safer - having a constant 6vdc connected to the relay contacts or the coil. There is also a capacitor in the circuit. not sure where it fits in.

Skip Lackie
07-27-2017, 05:54 PM
The horn mechanism is isolated from the assembly. Haven't found a third wire. Assembly getting it's ground by being bolted to the truck.

Trying to figure out which way is safer - having a constant 6vdc connected to the relay contacts or the coil. There is also a capacitor in the circuit. not sure where it fits in.

Didn't mean to imply there was a third wire -- agree that horn is grounded by getting mounted. Suspect the OEM system had constant 6vdc to the relay.