Horn no worky

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James Dwan
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Location: Dallas, Texas
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Horn no worky

Post by James Dwan » Thu May 12, 2011 7:52 pm

So I removed my windshield to do some POR-15 and the dash to get to the rat's nest so I could run new wires, which included removing the two bolts that secured the steering column to the dash.
Now the horn doesn't work. The problem appears to be between the fuse box and the horn. I have power to fuse # 11 because my brake lights and indicator work and I tested the horn itself. The ground wire under the button is snug.
I looked on the wiring diagram and it shows the wire from the horn going into a "T" connector but I can't find one.
I need to get it fixed so I can get an inspection sticker on Sat!
Any ideas?
'73/'77 Westfakia
'78 Super Vert
'59 23 Window Deluxe

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Hippie
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Location: 41º 35' 27" N, 93º 37' 15" W
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Re: Horn no worky

Post by Hippie » Fri May 13, 2011 8:13 am

Isn't there a push-on connector under the bus that feeds into the steering column at the bottom? Maybe that came loose.
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James Dwan
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Re: Horn no worky

Post by James Dwan » Sat May 14, 2011 5:31 am

Yeah I replaced that ground a year ago with a fresh one.

Well now I am stumped. The black and yellow wire was secured the whole time and is getting power at the fuse block.

I ran a lead from the # 11 fuse to the horn. Nothing. Then I took that off and ran a ground from the horn to the chassis. Nothing. Then I ran the hot lead to the horn AND the ground to the chassis and it worked.

Somehow BOTH wires going to the horn aren't working. I lost my tester so all I have is a test light so as far as I can tell I have a problem with both somehow. I did notice a VERY small spark when I ran the hot lead only to the horn which made me think it was a ground issue.

The ground for the horn as far as I can tell is in 2 places one at the bottom near the steering box and then the spongy metal piece under the horn ring.
So if I run a new wire to the horn (I'd rather not) I still have to figure out the ground issue with the horn button.

I don't understand how something so simple could stop working when I took the dash out.

BTW where does the ground wire on the horn go to? It disappears into the loom.
'73/'77 Westfakia
'78 Super Vert
'59 23 Window Deluxe

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Hippie
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Location: 41º 35' 27" N, 93º 37' 15" W
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Re: Horn no worky

Post by Hippie » Sat May 14, 2011 12:37 pm

That is weird. No clue where the ground goes after the loom.
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Amskeptic
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Re: Horn no worky

Post by Amskeptic » Wed May 18, 2011 7:54 am

James Dwan wrote:Yeah I replaced that ground a year ago with a fresh one.

Well now I am stumped. The black and yellow wire was secured the whole time and is getting power at the fuse block.

I ran a lead from the # 11 fuse to the horn. Nothing. Then I took that off and ran a ground from the horn to the chassis. Nothing. Then I ran the hot lead to the horn AND the ground to the chassis and it worked.

Somehow BOTH wires going to the horn aren't working. I lost my tester so all I have is a test light so as far as I can tell I have a problem with both somehow. I did notice a VERY small spark when I ran the hot lead only to the horn which made me think it was a ground issue.

The ground for the horn as far as I can tell is in 2 places one at the bottom near the steering box and then the spongy metal piece under the horn ring.
So if I run a new wire to the horn (I'd rather not) I still have to figure out the ground issue with the horn button.

I don't understand how something so simple could stop working when I took the dash out.

BTW where does the ground wire on the horn go to? It disappears into the loom.
James, trouble-shooting the horn should be easy enough.
The horn (+) terminal is hot whenever the ignition is on. Verify again.
Now the other horn terminal (-) should blast the horn when you ground it using a test wire. This ground circuit goes from the horn (-) to the steering column support and up to the brush. The brush can stop electrical ground path the the steering wheel ring just by the grease getting old. I clean and polish the brush and the steering wheel ring, then use DeOx gel as both a lubricant (important) and a conductivity enhancer.
Image

The electrical path to ground ends at the horn button ring-to-steering wheel. The steering wheel is NOT necessarily grounded! It rides on a rubber coupler at the bottom and it is suspended by rubber bush in the column support. Get your test wire just a piece of wire and turn on the ignition. Run your test wire from the spade on the horn ring to any nearby guaranteed good metal. If the horn sounds, then you may have a chafing or broken wire between the steering shaft and steering box. It goes kitty-korner from steering wheel shaft flange to steering box flange.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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jmstu76
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Location: Edmond, Oklahoma
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Re: Horn no worky

Post by jmstu76 » Wed Mar 23, 2016 9:41 am

can the rubber bush in the column support wear out causing the horn to ground through the column?

I have a horn that blares when I move the wheel left or right. I am trying to figure out where it is grounding prematurely.
James
1976 2.0L FI with Hydraulic lifters

Edmond, OK
(405) 623-2191

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Amskeptic
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Re: Horn no worky

Post by Amskeptic » Wed Mar 23, 2016 6:48 pm

jmstu76 wrote:can the rubber bush in the column support wear out causing the horn to ground through the column?

I have a horn that blares when I move the wheel left or right. I am trying to figure out where it is grounding prematurely.
Look from underneath the car at the steering shaft coming out from the column tube. If the shaft appears to be too close to the column tube, loosen the big column support on the floorboard (two screws) and try to center the column tube around the steering shaft.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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jmstu76
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Location: Edmond, Oklahoma
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Re: Horn no worky

Post by jmstu76 » Wed Mar 23, 2016 7:13 pm

Amskeptic wrote:
jmstu76 wrote:can the rubber bush in the column support wear out causing the horn to ground through the column?

I have a horn that blares when I move the wheel left or right. I am trying to figure out where it is grounding prematurely.
Look from underneath the car at the steering shaft coming out from the column tube. If the shaft appears to be too close to the column tube, loosen the big column support on the floorboard (two screws) and try to center the column tube around the steering shaft.
Colin
I have loosened those screws before when I did my rag joint. It seems to not want to center up anymore. in the past when I hit large bumps I can hear the steering shaft rattle against the steering tube.

I am going to guess that you are answering my question due to my symptoms. Can you tell me if the bushing in the column is replaceable or serviceable?
James
1976 2.0L FI with Hydraulic lifters

Edmond, OK
(405) 623-2191

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Amskeptic
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Re: Horn no worky

Post by Amskeptic » Wed Mar 23, 2016 7:24 pm

jmstu76 wrote:Can you tell me if the bushing in the column is replaceable or serviceable?
It is a big rubber donut that is almost indestructible, held in with a circlip, and very unlikely to offer you an intermittent horn ground.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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jmstu76
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Location: Edmond, Oklahoma
Status: Offline

Re: Horn no worky

Post by jmstu76 » Wed Mar 23, 2016 7:40 pm

So I'm trying to learn how my horn works. Late model bus. Positive power to the horn is supply through the turn signal switch. Power comes up from the brass "spring" on the top of the turn signal switch. It contacts the brass ring on the bottom of the steering wheel and then power is transfered up to the button ring by the black wire which fits over the tap on the button ring. When horn is pushed, circuit is completed by the ground traveling down the steering shaft, not tube, jumping across the rubber coupler by the jumper wire and grounding out through the steering box.

Is that correct or am I missing something?
James
1976 2.0L FI with Hydraulic lifters

Edmond, OK
(405) 623-2191

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jmstu76
Getting Hooked!
Location: Edmond, Oklahoma
Status: Offline

Re: Horn no worky

Post by jmstu76 » Wed Mar 23, 2016 7:54 pm

just went out and retraced everything and attemped to center the tube around the steering shaft. turns to the left don't blare the horn, turns to the right do.

Also, If I grab my steering wheel at the 12 and 6 position and rock it forward and back (a non natural movement of the steering wheel) the horn blares with the rocks. Must insulate the steering shaft from the outer column.
James
1976 2.0L FI with Hydraulic lifters

Edmond, OK
(405) 623-2191

User avatar
Amskeptic
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Re: Horn no worky

Post by Amskeptic » Wed Mar 23, 2016 7:55 pm

jmstu76 wrote:So I'm trying to learn how my horn works. Late model bus. Positive power to the horn is supply through the turn signal switch. Power comes up from the brass "spring" on the top of the turn signal switch. It contacts the brass ring on the bottom of the steering wheel and then power is transfered up to the button ring by the black wire which fits over the tap on the button ring. When horn is pushed, circuit is completed by the ground traveling down the steering shaft, not tube, jumping across the rubber coupler by the jumper wire and grounding out through the steering box.

Is that correct or am I missing something?
The hot side of the circuit is 12 volts from ignition switch directly to horn terminal. If ignition is on, horn has 12 volts!

The switch is on the ground side of the circuit. That means the other horn terminal is seeking a path to ground. Its wire goes to the steering brush under the brass ring on the steering wheel. When you push the horn button, it connects the brass ring-delivered-horn-terminal-in-search-of-a-ground to the horn button ring that has the spade and wire that grounds the circuit at the steering coupler bolt.
Colin
BobD - 78 Bus . . . 112,730 miles
Chloe - 70 bus . . . 217,593 miles
Naranja - 77 Westy . . . 142,970 miles
Pluck - 1973 Squareback . . . . . . 55,600 miles
Alexus - 91 Lexus LS400 . . . 96,675 miles

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