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Discussion Starter #1
I have a 2344 locomotive and the horn does not work. I don't know exactly how the horn works. Having to use a battery is strange to me when you have a power source. Anyway...

Using a 1033 90 watt transformer:

When I use the whistle lever the relay closes
I have continuity from the truck to the horn case
There is 1.5 volts to the post that goes to the horn on the relay if the relay is open or closed
I thought there would be zero volts at that post until the relay is closed
The horn does not work at all

I have not taken the horn itself apart.... trying to avoid that because I do not know what is inside.

Everything motors, etc., are very clean for this old locomotive.
Thank you,
Dean
 

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First isolate and check the horn. Unsolder the horn wire from the relay. Get a good battery and touch the negative battery terminal to the metal body of the horn itself. Touch the horn wire to the battery positive terminal. The horn should blow. If it does not, the horn is faulty. The electrical schematic is here.

If the horn works, the entire battery, relay and horn assemblies may need to be removed and any dirt or corrosion between all of the mating parts will need to be cleaned off. The horn works on 1.5 volts DC; that is why you need a battery, and that is why the entire electrical path for the battery must be clean. The contacts of the relay must be clean and touching properly when the relay closes.

Once you know the horn functions while isolated, and the entire electrical path is clean, the horn should blow when you close the relay contacts by hand.

Larry
 

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Hobo for Life
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Not sure about the voltage, but make sure the relay is all the way closed, try pushing up on it. The relay can also get dirty, try putting a small piece of cardboard in between it, close then pull the cardboard out. Think matchbook with. Repeat until the relay look clean. Try that first, other will know about the voltage. Also check the wires and grounds.
 

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Theoretically the wire can stay connected to the relay, but if the horn does not work, disconnect the wire to insure the horn is completely isolated and that nothing can interfere with the test.

Larry
 

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Get a 9 volt batter and see if the horn will work with it.

Also, with power on the horn, try tapping it with the handle of a screwdriver. Sometimes a jar will get the horn working again. You may have to adjust the screw that is on the back of the horn. If the horn makes noise when you tap it with the screwdriver, keep tapping it and adjust the screw.
 

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There are some videos on YouTube about repairing the horns. I have only taken one apart, and it no repairable. I believe tapping with the screwdriver is as good as taking them apart.
 

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Railroad Tycoon
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My kind of repair... get a bigger hammer :D
Reminds me of a song......If I had a hammer......

The trick is that you need an assortment of hammers and to start out with the smallest you have and work your way up.

If the last hammer in your assortment comes close to the size of this one, it will fix the horn for good.
No more problem. :p

AmitandTsur2006OhioUSA070.jpg
 

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Discussion Starter #12
Found the video and went through his procedure and nada.
I have to isolate the horn as mentioned above and make sure it is the horn.
If it is I guess I need to get a new horn... thanks for a source.

I am stumped though because I have continuity from the rectifier to the horn so I know the wire is good. What I am not sure of is that I have 1.5 volts at the hook-up. I saw it earlier and now I am not seeing it. The battery is new and checked... so the hunt goes on.
Tomorrow is another day...
 

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Did you remove the horn? They have to be grounded, right. Just trying to rule out a simple thing like a good ground.
 

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Yard Master & Research
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The horn wire gets corroded inside. If it doesn't work, hit it with a hair dryer. It may be just enough. One word on repro horns. I got one that sounded sick. I have used a 9 to 12 volt DC wal wart to jump it.

In order for the horn to work it has to vibrate. So playing with the adjustment might help.
 

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If you have a voltmeter, set it to read DC volts and hook the black (-) lead to the horn body. With the battery in the locomotive, touch the red (+) lead of the voltmeter to the metal body of the relay. With a fresh battery you should get a 1.5 - 1.6 volt reading.

Anything significantly less indicates a bad circuit for the battery.

The relay movable contact closes the circuit between the battery + (on the metal body of the relay) and the horn power wire.

You need to isolate the horn first and determine if it functions correctly before you start chasing electrons.

Larry
 

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I have worked on these horns and wiring directly is a good idea. Working the adjustment screw while tapping the horn when it is powered should get it to vibrate causing it to start sounding. If not then the horn can be taken apart and it is likely a corroded connection or the wire may have simply popped loose since some are only crimped on.
 

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Discussion Starter #20
Well guys, once again you saved the day. Once isolated I got the horn to work. I took it apart and cleaned the contacts checked continuity and tried the test as shown in the video. No dice. Sprayed it with electrical contact cleaner, put it back together and it worked...
Not real sure what I did. After a few misfires I got it back together and it is now working with the transformer.

Thanks again... I really needed the help.

This is a strong C-7, A-B-A set and is now ready sell.
Dean
 
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