What gives

Gooseloony

Gooseloony

Senior Member
Another darn horn question--took it all apart, cleaned it up (armature, brushes etc.), replaced gaskets, put all back together and guess what? You're right, it doesn't work! Read 6v from one connector on the horn to frame; but when I connect hot leg to horn and then ground other connector to frame I just get sparks and armature doesn't turn at all. Note: the armature turn easily with my finger, also the horn worked before just sounded lousy. I'm also testing it sitting with horn facing down and without cover, would that matter? Thank you
 
Hook one side to one side of the contact and the other to the other side of the contact, not the horn frame. The contacts are insulated from each other. Rod
 
Like this.

Bob
 

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Thank you Bob that's a great photo but issue is not which terminal to land on but that the armature is not turning. From what I understand it doesn't matter which terminal you land on because one side is "hot" from battery and the other side goes to ground (frame) up through steering column to horn button. I am just trying to make it work by bypassing the horn button and going directly to the frame near the horn for testing purposes. Sorry to all for the first explaination. But I don't understand the spark without movement of the armature which moves freely by turning it with a finger.
 
I've reposted Bob's photo, showing the electrical path in yellow. Place the horn on a bench and use an ordinary 6v battery charger to test it. Use a volt/ohmmeter for the following tests.

1. None of the electrical points shown in yellow should have continuity to the horn frame
2. No continuity from either connector at the bottom and the frame (#1)
3. Resistance between the two connectors at the bottom should be less than 100 ohms
4. 6v at the connectors should turn the armature

If either #1 or #2 fails, then you have missed an insulator, as Tom said, or there is a stray wire, or misplaced screw grounding things out, or shorted field coils, or shorted armature.
 

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It sounds like you have a short. All of the wiring and paths do not ground to the horn frame. All current is insulated from the horn. The horn frame is not a ground.
 
I think I see the problem from what Tom said and by looking at Ray's photo. Little late tonight so I'll fix the issue and give it another go tomorrow and post again. Thank you guys and Ray the photo was really helpful, for a newby like myself photos are golden!
 
I put all the parts back together (including the insulating washers, ha) and tested with leads of the horn wires--it works but shouldn't it NOT work until I push the horn button on the steering wheel?
 
the horn is hot at all times just like your modern car. Should only blow when the horn button is pressed. Its common for the horn button itself to be shorted out or the wire inside the horn rod has worn a bare spot.

Could try flicking the button and see if its just stuck or hung up somewhere but sounds like you have some wire tracing/continuity checks to do...
 
Gooseloony said:
I put all the parts back together (including the insulating washers, ha) and tested with leads of the horn wires--it works but shouldn't it NOT work until I push the horn button on the steering wheel?
Click to expand...

Remove the wires. Check for voltage on the wires. There should only be one with power. Put this power wire in the horn first in one holder then in the other holder and see it it starts to blow. If yes the horn has a short to ground. If no then the wire to the button (or Button) is shorted to ground.
 
Been busy so running a little late on reporting back--RESULTS: with fuse removed I get continuity from hot leg to car frame and NO continuity on other leg (horn button I presume) to car frame. I think this tells me I have a short on hot leg (but not blowing fuse) and the wire to horn button is ok---not grounding out. Does that all make sense with how I described it?
 
Yep, you have a short. Slip a piece of paper between each brush and the commutator. Now check each brush to ground, and check the commutator to ground.
Shouldn't take long to locate the short.
 
Tom the continuity is from HOT(without being connected to horn) to car frame. So it's not in the horn itself, does that sound right? The good news is it doesn't appear to be in wire running up to horn button or at the horn button.
 
Gooseloony said:
Tom the continuity is from HOT(without being connected to horn) to car frame. So it's not in the horn itself, does that sound right? The good news is it doesn't appear to be in wire running up to horn button or at the horn button.
Click to expand...

The horn should be isolated from body, that is there should be NO continuity on either side of the connector to the car body.

The hot goes into the horn, comes out of the horn and is grounded at the horn button on the steering shaft.

So, on one wire to the horn you should have battery voltage.
The other wire should have no voltage and NO continuity to the body until the horn button is pressed.
 
Are you mixing up "CONTINUITY" with "VOLTAGE"?

It's as Mike said.
If the hot wire has continuity to the frame, then that means it has a short and will smoke some wires.
 
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