Anyone know how to get a Grant horn button to function and not just spew sparks?

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Murdoc

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I've burned through two sets of contact rings and plates under my horn button. When I press on the button I can hear a feeble sound coming from the hi and low pitch horn devices under the hood and then blue sparks shooting from under my horn button. I've searched the web and I'm still totally stumped. Di-electric grease on the contacts seemed to work briefly, but definitely not a permanent solution.

Steering wheels DSC_4074.jpg

 

Bentworker

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have a pic of the horn button itself?  They need an isolated contact - IE one side cannot be grounded.

 

turtle5353

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lol!! Good luck. I have removed many of those over the years.  Piss poor design.  Steering wheels are nice but their horn set up blows!!!

 

Murdoc

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Here's what the inside of the button looks like currently.

IMG_9845.jpg

 

Galucha

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I had the same symptoms. The issue I had with mine was that the copper contact plate that is glued onto the metal piece was off center. Terrible QC. I compared it to an old one that was made about 15 years prior and you could tell that they didn't position the contact plate correctly. It was at least 1/8" off center.

 

Bentworker

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I am no grant wheel expert but did you follow the two wire setup shown in these instructions? 

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rackerm

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Modified 1970 Mach 1 M-Code with a 351C 4v Manual

Here's what the inside of the button looks like currently.

View attachment 55218
Make sure your horn mounting brackets are bolted tight to clean unpainted factory holes in the RH inner fender apron. The square wire connectors and the horn's blade connectors are not corroded.

Just like with headlights, I always suggest taking the load off the original factory circuit and switch. The horn has a 20 amp circuit with 14 gauged wire and carries a heavy load from the fuse box thru the column and back out to the horns. It is frequently a source for weak sounding or intermittent working horn issues. I suggest installing a relay with a fuse either under the dash, or get a weather proof relay and socket and install it our near the horns. Run a 10 or 12 gauged wire from the battery to the fuse (20 amp) and then to the relay (pin 30), and run either new 12 gauge wire or use the last section of the original 14 gauge wire from the relay (pin 87) to reconnect the horns. Connect the original horn 12v source (14 gauge blue/yellow stripe) wire from the horn switch and goes thru the firewall to the relay (pin 86 pos). Connect a 14 gauge black wire relay (pin 85 neg) to a good ground source on the chassis. Locate the relay either near the horns or the battery. Either way you will be running a new 12 or 14 gauged wire from the battery to the horn location. The relay will be located on one end or the other of the wire. In my opinion, having the relay near the horns make the splicing into the 14 gauge blue/yellow stripe wire to connect the relay easier.

 

midlife

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My guess, based upon the picture, is that the rivet on the left side can ground against the steering wheel itself (ground plane) where the back side of the rivet is.  Try putting some black electrical tape on the back side of the rivet.

I had a Grant Signature series wheel on my 66, and never had a lick of a problem with the horn.  That series of wheels have good horn systems.

 

jscott

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Aus73Mach1

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Q code. 351-4V
C6 Auto, 3.25 Rear Axle, AC, Power steering.
I had a problem with stripped threads in the hub and purchased 2 kits to suit. One was so bad I got a refund. The build quality is probably some of the worst I've seen. The photos show the new parts straight out of the box. The wires on both slip rings are soldered in the path of the slip ring pins. I ended up having to remove the original slip ring plate and glue it onto the new hub.

What kit number did you buy?

It appears you may have a direct short circuit. First, check that the horns work. Disconnect the wires, remove the steering wheel and hub. That done, bridge the 2 slip ring pins and the horns should work. If not and you get sparks instead, the problem is in the wiring somewhere else. I have instructions and can provide more photos if you need them for the Grant kit.

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Murdoc

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Sorry, what do you mean by "bridge the 2 slip ring pins"?

 

Omie01

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Also make sure that your steering wheel nut is not grounding out on any of the copper, this is what I ran into. The peaks of the hex just touched the copper enough to pop my fuses. Had to grind a little off the nut.

 

Mister 4x4

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Wow - I've never had issues with any Grant wheels.  My Jeep has a Challenger-series (no issues), my Mach 1 has a foam grip version of the wheel in the original post, and my '82 Mustang also had a Challenger-series (granted, the horn button was on the signal stalk - glad they moved away from that design).

 

Kilgon

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Several things to try and do if you are going to keep it.    The first  thing you need to remember is that there are no "contacts" on this  type of set up.  It's the same as taking a pair of jumper cables and touching the ends together - sparkola!   

I would take the lead on the left and turn it around 45 degrees so its over disc.  I would also make sure that your horns are grounded good.  You can check out how well your horn's are working by disconnecting them and then take a piece of wire and run it directly from the horn to the positive side of the battery.  You should get a nice solid steady tone.    If not then it could be a indication of a bad ground or the horn failing. Check each one out.

I would also do away with the spring in the center of the button and put some foam underneath the top plate to keep the plates separated.  I used a little extra to ensure that contact can't be made unless you are "pressing" on the button. This will also stop your horn button from popping off and causing any problems.  I just lost both of my horns due to this happening at the hot road power tour while it was parked.  The button came off letting the plates come together and the horns went off untilled they fried. 

I have gotten few sparks ever now and then when I don't press hard and make a solid contact.

Here is how mine is set up.

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Flatback72

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Also make sure that your steering wheel nut is not grounding out on any of the copper, this is what I ran into. The peaks of the hex just touched the copper enough to pop my fuses. Had to grind a little off the nut.
This was also the case with my Grant Challenger set-up. At random times while turning the wheel I would hear one of the flasher cans operating in the dash, though the blinkers were never flashing when this happened. Turns out the peaks of the hex on the nut were just touching the horn copper, enough to catch a bit of current and somehow direct it to the blinker switch circuit. So I ground off the peaks a little bit and never had the problem again!

 
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