[98 SNAKE EATER]

The horn in my T/A has only worked sporadically since I've had her and never when I needed it

Checked the relay and it worked fine when jumped, but I wasn't able to get a trigger signal from the horn during testing

Found a random black wire coming out of the harness under the dash with some insulation missing

Probed it with a test light and it actually triggered the horns from a ground (scared the sh!t out of me and nearly stabbed myself with the damn test light)

Removed the button pad to have a looksee what's inside as I've never had one of these wheels apart before

Oddly enough, it actually works more often with the key removed than when the car is running

Here's a little video:

https://www.youtube.com/watch?v=RVGutv8XF_M


Is there a writeup showing what's involved with testing/replacing the switch?

[Formulabruce]

The black wire comes up through column and end up on a spring loaded pin that presses on the horn extension in the hub. This wire grounds the relay which turns on the horn. Take the plastic horn extention out of the hub and you can see whats going on easily

[fbody_mike]

Key removed so that the steering lock pin is against the locking plate?
With the steering locked, try moving the steering wheel so that the pin is centered in whatever tooth of the lock plate it is in, so that the pin is not making electrical contact with that plate, and try out the horn. With the steering locked, turn the wheel hard to the right, press the horn, turn the wheel hard to the left hit the horn, then try to find that tiny movement in between and see how reliable the horn is.
Could be a poorly grounded steering column, coupled with a dirty rotor for the spring contact, and you will get just enough resistance to keep the relay from energizing.
Also make sure the ground strap on the rag joint is there and not corroded.

[98 SNAKE EATER]

OK, I eyeballed the rag joint, but didn't see a ground strap (kinda hard to make anything out with all the crud around it)

I tell you, I've probably changed a dozen of these joints over the years and never really paid attention to the ground (doh)

Ran a test light to the top of the shaft and it had continuity

Then I wrapped a 10gauge wire around it and ran it straight to battery ground, but it made no difference

With the key out and the steering locked, I tried it again and got nothing, but when I put tension on the wheel to the left, the horn button worked consistently (see video)

https://www.youtube.com/watch?v=1WS3jnfhYtw


Way too hot to fiddle with it anymore today

[98 SNAKE EATER]

SUCCESS!!

Decided to take her apart today and found that the contact spring was very weak and wasn't putting enough tension on the contact.

Removed the contact and tried stretching out the spring, but it still didn't have enough tension, so as a quick fix, I stuffed the hole with some coiled up copper wire, then replaced the spring and it now has good tension on the contact

Also gave the rotor a little cleaning with a wire wheel before putting it all together and she's good to go


Here's a little video

https://www.youtube.com/watch?v=ZNOmRwv95Mc

[fbody_mike]

Glad to hear you got it working right. I think that rotor was your main issue, that was pretty dirty. Everything in the circuit, the spring, the pin, the rotor, the column, the rag joint, they all add up to a point where you will find the threshold of resistance that will stop the relay from engaging.
Make sure to road test it too.

[98 SNAKE EATER]

Originally Posted by fbody_mike

Glad to hear you got it working right. I think that rotor was your main issue, that was pretty dirty. Everything in the circuit, the spring, the pin, the rotor, the column, the rag joint, they all add up to a point where you will find the threshold of resistance that will stop the relay from engaging.
Make sure to road test it too.

Although the rotor was a bit corroded, it still had continuity all around.

It was just the pin not extending out far enough to make contact with it.

Tested it at all lock positions and speeds

Even made a hard pass through the gears with the horn s blaring all the way and she didn't skip a beat.

Unfortunately, the alternator decided to seize up on me on the way home.

Managed to pick one up at Advance and throw it in before it got dark.

[71GP76TA]

Originally Posted by 98 SNAKE EATER

Although the rotor was a bit corroded, it still had continuity all around.

It was just the pin not extending out far enough to make contact with it.

Tested it at all lock positions and speeds

Even made a hard pass through the gears with the horn s blaring all the way and she didn't skip a beat.

Unfortunately, the alternator decided to seize up on me on the way home.

Managed to pick one up at Advance and throw it in before it got dark.

Save the old alternator. Its original to the car. Those open face alternators are worth $$$$

[98 SNAKE EATER]

Originally Posted by 71GP76TA

Save the old alternator. Its original to the car. Those open face alternators are worth $$$$

Yeah, I kept the original

Should've brought it back with me to NY to rebuild, but Ill get to it next year.

The cheap replacement made noise right out of the box, but got me home that night.

I'll exchange it when I get back