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TR6 TR6 horn help please

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I

ichthos

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Got one of two horns working so far. In addition, I have no electricity to the horns. I am trying to trace this down. If I run a light test lead from the horn button to ground (steering shaft or nut), shouldn't it light up? Any suggestions or help is greatly appreciated.
Kevin
 
The horns are individually grounded (black); they get power from the horn relay (purple/ yellow).
The horn relay gets power from the fuse block (purple wire) and grounds thru the horn button by completeing the ground circuit to the steering rack.
What you describe sounds like there will be no power, just the ground. So I don't think a test lamp would light under those conditions.

:eeek: Never mind. Don't you have a 69 ?
 
Yes, Poolboy, I have a 69. I am don't think I have a horn relay (although I was thinking of adding one later.)I know they are different, but on my Bugeye, when I touch the horn brush to a ground, it lights up. The bottom line is I do not really understand how the wiring works for the horns on this car, so I can't logically figure it out.
Kevin
 
Having a look at the schematic for 69 cars, I see you get power directly to the horns thru a purple wire originating at the fuse box.

The horn button when pushed connects the purple/black wire on the horns to a ground on the steering rack.

So everything associated with the steering column and rack is for the grounding part of the horn circuit.
 
The connection at the horn wont show 12v. try a continuity test, just to get your meter to beep. You said one horn worked,try using jumper wire to the other horn to rule out a bad horn. I just went through this with my 76. Be sure the ground wire is hooked up at the steering rack. The wire should be at the top of the adjusting screw on the rack.
 
KSIS, like myself in my first post, is thinking it's like the post 69 cars.
69's have no horn relay. There is always power to the horns, just not a ground until the horn button is depressed.
Have a look at the wiring schematic.
The power (+) is shared by both horns and the ground wire (-) is also shared, but the horn button must be depressed to complete the circuit.
 
Yeah, simple enough Ken. I spent timing looking for a bad connection in a similar situation only to later find out it was the horn hence my suggestion. But agree this should be pretty easy to run down.
 
Kevin,
From how the thread has explained it, the TR horns work the same way the your BE horns do, i.e. 12V power from the fuse box to the horns, then a wire back to the horn button, and grounding through the steering column. Only difference is color of the wires and two horns instead of one.
Good luck.
Scott in CA
 
The grounding wire is hooked up to the steering rack. I took it off and cleaned it just to make sure. Scott, I did have both horn connections (but not horns) working at one point in conjunction with the horn button (after all your help with my Bugeye), but then had to take the steering column apart. I was also working on the dash (found I had a bad voltage regulator on the speedometer),so who knows what I messed up. I took out both horns and hooked them up to the battery. I Ohmed both horns. Of course the working horn checked out fine, and the other did not. I am working on that horn now - the "points" look bad on that horn. I do have one horn working to test things out.

So here is what I have now. I have a solid purple wire and purple/black wire going to each horn. When I hook up my test light from the solid purple wire to ground it lights up at both horn hook ups. From what you stated, Poolboy, this car does seem to be set up the same as my bugeye. When I hook up the horn brush to ground, my test light lights up on the Bugeye. On the TR6, it does not do this. Doesn't this basically mean there is a problem somewhere in the steering column? I know this seems simple for you guys, but how do I find the bad connection then?

Kevin
 
There are a couple of spots where the ground connection might be broken along the steering column.
One would be the braided "ground strap", Moss # 667-095 connecting one side of the steering column to the section on the other side of the flexible coupling, Moss 667-390.
Others would be in the wiring harness from the horn slip ring's wire connection Moss 667-590.

Then again it could be that the inoperative horn is the entire problem; just like a bad Christmas tree light affects the whole string of lights.
You might ought to get it working first before chasing down the other suspects
 
Kevin - just to be clear I wasn't trying to suggest it should only take a furtive glance to figure it out, just that it is a pretty simple circuit. I just rewired a flasher unit on the MGC when it turns out it just had a bad ground, so completely understand this can be frustrating.

One idea is to run to a know good ground someplace other than the column, if that work then you know the horns are ok and the column is the issue.
 
That makes me feel better, tdskip. I know everyone says how simple these cars are, but I admit I spend hours trying to figure things out - electrically and otherwise. In most cases so far it has ended up being a grounding problem with almost all my electrical problems. I have one horn I know works well. I think what I will do is get the other horn working correctly as Poolboy suggested, and then come back for advice. I have got to finish my original bugeye horn first. Thanks guys.
Kevin
 
It is the grounds more often than not, and checking the item in question before it goes into the circuit is also usually worthwhile. Replacement horns that are louder are cheap, albeit not completely stock looking, if the one horn doesn't want to cooperate.

And no problem on working on the Bugeye first, I need to get my Bugeye MC back in, so just ping back here when you are ready.
 
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