A question for the more electrically-minded crowd....

[Marshall V. Daut]

As I have posted many times before, electrical issues are not my strong suit. 'Been my Waterloo for years working on cars. I just don't "get" how electricity works in practical applications. Do you know anyone who flunked 8th Grade Electricity Shop? Well, you do NOW!!!

Anyway, see if I am correctly envisioning this proposed solution to an electrical problem I am having with a light switch and rod. The horn checks out o.k., but will not work when the button is pressed. I checked all wiring and the inside of the switch body. Nothing wrong or out of place. The steering box had to be removed for rebuilding, so this gave me the opportunity to remove the light switch rod, disassemble the horn button and clean oxidation and rust off the contacts. The wire running through the rod housing was still connected, not broken or frayed. The tip looks undamaged, as many are. Before I reinstall the rod in the steering column and put them both back into the CLOSED car, I want to check that the button will now function properly. The horn is a little scary inside with lots of blackened wiring and armature. I don't want to hook up a test battery incorrectly and burn up what's left in the horn' s life. 'Gotta get it right the first time. So...

The light switch rod is lying on the garage floor. Do I run a wire from the battery's negative post to one horn terminal, clamp a wire from the battery's positive post to the light switch rod to provide a ground, and a wire from the tip of the light switch rod to the other horn terminal? Will pressing the horn button then close the circuit and make the horn work? If I have this all wrong, how DO I route the wires to test the horn button's functionality?

'Sorry for this basic electrical question that is probably causing the electrical gurus in the audience to roll their eyes skywards, but we can't be experts in all aspects of automotive repair. I'm living proof of that...
Marshall, the Village Idiot

[Y-Blockhead]

Marshall, the wiring for the horn is 6V+ > horn from generator (yellow wire), wire from horn to horn rod inside light switch (blue with yellow tracer) > up column > horn button > ground 6V- when you push it. The horn is not grounded. Hope all that makes sense.

[Bob C]

Sounds like you have it right to me.

[Ayers1]

Marshall, there is an easier way to check the rod as long as you have access to an ohm meter. You should be able to put 1 clip of the meter on the shaft of the rod and hold the other one on the contact at the bottom of the rod. When you press the button the ohms reading should go from "infinite " or open to zero which means the circuit is closed. If it does this then your horn should work fine.

[larry harding]

don't be surprised if you have a problem in that two piece housing that has the light as well as the horn connections. i've had some headaches getting the lights to work and the horn not to short and blow when not wanted. we are talking 20's technology, but henry kept this switch for a time after the a. not the best engineered part of the a in my experience.

[Marshall V. Daut]

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The headlights and taillights work. The horn spring plunger was where it should be. I think the problem lies in the horn button and its contacts, which I have cleaned. It just needs to be tested.

I don't own an Ohm meter (You KNOW why!!! It's that electrical mental roadblock thing again with me! ), but the shop where I am working on the car might have one. I'll check tomorrow.

Thanks to all for the advice so far. I'd still like to physically hook up the light rod to a battery and horn just for grins and giggles, even if the horn button checks out o.k. with an Ohm meter. It's the masochist in me.
M.

[Joe K]

They periodically give out FREE Volt-Ohm testers at HarborFreight - when you buy something of larger price. They're a little fragile, breaking primarily at the "probes." But the price is right. You can test voltage both AC and DC AND you can test various degrees of resistance. Another small downside is they use a 9v "transistor battery."

The horn is unique in that it operates on the "downstream side" - you press the button and it completes the circuit to ground.

One issue I've seen is that the horn rod is not contacting the center contact of the circular plate. You can test this by removing the circular plate and use a wire (or the meter probes) to touch simultaneously the center of the circular plate AND the contact on the end of the rod. This checks both the circuit and the horn rod when the button is pressed.

Similarly, you can use the probe/wire and go from the center of the circular plate directly to the car chassis (or a proven ground spot usually a galvanized bolt head.) This checks everything but the rod.

I would lay wager that you may not have exactly the right rod - there are five different lengths/patterns determined by your particular steering gear/length of steering wheel shaft.

Joe K

[nkaminar]

1. Connect a wire from one side of the battery to one terminal in the horn.
2. Connect another wire from the other side of the battery to the outside of the horn rod.
3. Connect a third wire from the brass button at the end of the horn rod to the other terminal inside the horn. Make sure the third wire only attaches to the button and does not contact the outside of the horn rod. Some electrical tape will help.
4. If the horn works when you press the button then all is good and the sun will come up in the morning.
5. If not then there is something wrong with the horn or button. At which point, ask for help from an old man who grew up with crystal radio sets.
6. Go back to school and repeat your 8th grade electrical class.

[old31]

NK, I am in the same sinking electric boat as Marshall. No matter how many times I repeat 8th-grade electrical class, the ohmmeter always reads the same: ZERO!

Last week I spent days trying to get a horn to work. I took everything apart and it never worked. Come to find out that the horn adjustment knob on the outside of the horn was too tight. Duh.

I just don't understand how some people (like me) can get mechanical stuff, but yet be so dumb about electricity.

When you guys explain it you make it sound simple, kind of like me.

[Marshall V. Daut]

I doubt whether schools offer hands-on courses in anything as practical as electricity anymore. Not "relevant" enough for the new generations. Get one's hands dirty??? That's for somebody ELSE to do! Why take a useless course like electricity when you can take a course that teaches you how to feel good about yourself? Although I wasn't crazy about any of the four shop courses in 8th Grade (electrical, woodworking, metal working and drafting), even then I recognized that they gave me at least some extra skills that would come in handy in life. I guess such things are no longer considered worthwhile in current school curricula. Grumble, grumble, grumble...

Hey! Maybe "old31" and I had the same shop teacher for electricity??? That might explain why we are such dunces when it comes to solving electrical problems???

Back to the question at hand: I did measure the rod and steering shaft and they were a match to each other according to the Snyder's chart. They are the last one on the list, the Gemmer H option for 1930-31. I'll see if an Ohm meter will tell me what I need to know later today. I'll also hook up the battery to the horn and light rod to see if this final test will ease my mind.

Marshall

[katy]

Originally Posted by Marshall V. Daut

Hey! Maybe "old31" and I had the same shop teacher for electricity??? That might explain why we are such dunces when it comes to solving electrical problems???

Some "teachers" know how to teach and others just think they do.

[Marshall V. Daut]

"Those who can, do. Those who can't, teach".

'Not sure that's always true, but often enough through my public education path it WAS true. My 3rd and 4th Grade teachers would have made great women's Nazi concentration camp guards. They would have needed very little training for the job. 68 years later, I still have nightmares about those two years under their thumbs. Learning was put on "hold" during that time. Mere survival to reach the 5th Grade and a human teacher became of utmost importance. Thanks for the memories, Davenport Public School System!

M.

[jb-ob]

You never met Mrs. Reilly, most feared substitute teacher, no nonsense, lethal with a black board eraser.

Still respect that women, education needs to bring her type back.

[rotorwrench]

I burned up fuses in the basic electricity class in aviation maintenance school back in the day but I learned a lot more over the last 45 years or so.

The model A horns are shunt wound motors so they can be connected either way (not polarity sensitive). A test light is a good tool to check for power in a circuit but not so much when testing the ground side only. A small 6-volt bulb & socket can be wired into a complete circuit to test it when pushing the ground switch (horn button). A person just needs to be able to visualize the actual parts of the circuit where the current flows.

There also should be a copper bushing that seats into the top of the steering shaft. That helps the horn rod make a better ground contact to the steering shaft. They are available from most model A parts sources.

[Marshall V. Daut]

"You never met Mrs. Reilly, most feared substitute teacher, no nonsense, lethal with a black board eraser."

She must have been a cousin of our notorious grade school substitute teacher, whose very name struck fear into the hearts of every kid in the school system. When it was announced she'd be taking over for the next few days, more kids called in sick than during the entire flu season. Mrs. Nebergall. Doesn't the name just say it all??? The rumor went around that she tried out for the part of the Wicked Witch of the West in "The Wizard of Oz". 'Flew all the way from the Midwest to California to audition for the part. When the casting people saw her, they begged Margaret Hamilton to take the role of the evil witch so that they wouldn't have to deal with an even scarier-looking Mrs. Nebergall. So, she flew back to Iowa on her broomstick and remained the Wicked Witch of the Midwest until she died at the age of 250.
Rest in Peace, Mrs. Nebergall, wherever you are - you old battle axe!
Marshall
Added: I checked the cleaned and reassembled light switch rod and horn button today with an Ohm meter and there is now continuity! The tip needed some extra solder added, so I think we are good to go.

[jb-ob]

Man that was close ! Last week end we sprang the clocks ahead successfully and this week Marshall is tempting the electro-magnetic balance of the universe !

[Marshall V. Daut]

"...and this week Marshall is tempting the electro-magnetic balance of the universe !"

That's because I'm so ATTRACTIVE or maybe it's my MAGNETIC personality? N'yuck, n'yuck, n'yuk...
M.

[Jeff/Illinois]

Marshall, your substitute teacher was flying under an alias. Here is her picture as found in nature.

Ilse Koch--- 'The Bitch of Buchenwald' (also was proficient in electrical shop class)

A Beast and a Witch!

[Benson]

This was in the 50's in a small four room school house. Mrs. Lake had 4th and 5th grade.

Mrs. Lake was over weight and did not like to get up from her chair unless there was a fire drill or an actual fire, which actually happened when one of the resident "hoodlums" who had been held back twice was smoking in the restroom and stashed his lit "Cig" in the trash can.

Anyway when some one was smarting off Mrs. Lake's method of dealing with the problem was to throw what ever was handy on her desk at the offender.

Several of the more troublesome individuals kept her desk supplied with a number of magazines which they would steal from the local doctors office waiting room. (The reason for this will become clear later.)

On this day the Kid in front of me was "smarting off" and ignoring Mrs. Lake's attempts to restore order. This was an unusual day for her and she had used up all of magazines and erasers on her desk.

Mrs. Lake started to address the kid in front of me directly and I knew what was going to happen next.

She could not find a magazine or an eraser. The next thing I saw was a Webster's Unabridged full size Dictionary at the upper arc of it's flight coming toward us.

The trouble maker sitting in the desk in front of me ducked down and I raised up my desk top to a 45 degree angle and ducked under it.

The book hit my desk top which was at a 45 degree angle was launched right in the face of the girl sitting at desk behind me. She got black ink all over her when the ink bottle went flying.

Mrs. Lake tried to blame me for the problem but the principal did not buy her explanation.

Now whenever someone mentions Facebook I think about this day in fourth grade when I almost got "a book in the face"!

[Marshall V. Daut]

And you KNOW how it all ended for Ilse Koch, the Bitch of Buchenwald! Mrs. Nebergall should have joined her! What happened to Ilse, you ask? I don't want to leave you HANGING, but... Well, let's not go there.

O.K. Back to Model A stuff so that we can get into the SWING of things. Or is that a STRETCH?
M.