Horn trouble shooting

[kdavid]

I have a new oem relay. Recently painted the firewall and may not have a good ground. Does it even need to have a ground wire? I can get the horns to work by placing positive direct from the battery to the post on the horn and ground the horn body to the negative battery post. I'm not able to get the horn to work by using the buttons on the steering wheel. Any suggestions?c

 

[Degnol]

The horn relay operates on a ground. Like when you press on the horn button, it completes the ground circuit, so yes, you need a good ground.

 

[zags]

The horn relay operates on a ground. Like when you press on the horn button, it completes the ground circuit, so yes, you need a good ground.

Actually, the ground circuit is completed in the steering wheel when the horn button is pushed so no, the relay does not need to be grounded. Unhook the connector from the relay and use a test light clamped to ground to see of you have power from the wire at the "B" terminal.(Green w yellow) If not, check the fuse and wiring. If you do have power, place the clamp of the test light on the positive battery terminal and insert the probe end in to the connector for the "S" terminal. (Green w red). Push the horn button. The light should light up. If not you have a problem in the ground circuit. The most common problem is a dirty or broken horn contact in the steering wheel hub.
The wire colors are correct for my '70, I don't know if they are the same for yours.

 

[kdavid]

Tester

1. clamp connected to negative = light illuminated on tester touched to green/red
2. clamp connected to positive = light illuminated on tester touched green/white
3. I get nothing connecting green/yellow to either positive or negative
4. connecting the green/red to green/white activates light
5. fuse is good

 

[kdavid]

Connector on relay

With connector connected to the new relay:
1. Light illuminates and horn sounds when tester is on battery negative and probe touched to back of connector at green/yellow
2. Light illuminates with tester on battery negative and probe touching back of connector at the green/red
3. Light illuminates with tester on battery positive and probe touching back of connector at green/white
Buttons on the steering wheel do not activate horn.

 

[zags]

It looks like the wire to the horn button on yours is the green/yellow wire. That wire is not grounding when you push the button. I'd start by checking the connector that sticks out of the steering column under the dash. Ground it there and see of the horn works. If it does, take off the horn button, then the steering wheel if needed and see if the horn contacts are the cause.

 

[kdavid]

Intermittent horn buttons

I took about a five mile ride to Lowe's and tried the horn buttons. The left one worked! Then with multiple tries the other two started working. Then they just stopped for no reason. As I turned the steering wheel the buttons started working again. I'll check the ground under the dash as you suggest.

 

[tornadoalleycruiser]

Ul need to pull steering wheel and clean the contact that spins

Sent from my phone using IH8MUD

 

[kdavid]

clean contacts on steering wheel horn buttons

Yep....I think that is the problem. Both horns are working on all three buttons but not continuously. Need to clean contacts if I can get to them.

 

[kdavid]

Problem solved

On the back side of the steering wheel there are screws that are connected to each horn button. I loosened each screw slightly and moved them to remove any rust and corrosion that had built up. The buttons are working after that. I'll probably remove the screws completely and make sure that the contacts are clean of any rust.