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TR6 TR6 Horn

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Terry_M

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Hello
My horn would not work ,changed the stick-- still no go. Cleaned the fuse box terminals ,now the horn will not stop .I am thinking it is the horn relay--- Where would i find that ? if that is what it is If any one has a idea --This car as i have learned is a 74 body with an earlier wiring harness . The wiring diagrams are no help
Any help or direction would be appreciated
terry
 
If you have a Lucas relay it's about the size of a matchbox and it'll have a bunch of purple wires and it may be near the fusebox.
 
the wiring in this harness is faded ,some have been over sprayed many times the colours do not match the manual I think i have it a small box attached to the inner fender close to the fuse box maybe ? I will order a new unit to-day In the mean while is there something else i can check
thanks
terry
 
Yeah, the original relay replacements cost a few bucks and the old ones insides will probably clean up...Speaking of clean up...clean up the wires so you'll know what you are doing.
 
My TR6 is a 74,this spring i did some work underneath . I see at least three paint schemes ,perhaps three cars,i don't know. Last spring i bought a used ignition switch to fit a 74 ,it would not plug in I assume i have a 69-71 harness According to the Robert Bentley manual it shouldn't matter that much for the horn. I have been back in the harness far enough to see original colours. I believe i am plugged into the fuse box correctly according to RB I get horn immediately as soon as i plug into the fuse box I have the horn button apart ,so no connections at the steering wheel. Is this where the horn relay interrupts the circuit until the horn button closes
Terry
 
On the fuse box is there a brown wire feeding the fuse on one end and purple wires on the other side of the fuse ?
One of those purple wires wires should be feeding the relay at all times, but the horn won't blow until the purple/black wire on the relay is grounded....that's done with the horn button on the steering wheel which uses the actual steering column to reach ground.
If the horns are blowing, it's because there's a ground somewhere.
 
Yes i have brown feeding the fuse picked up by double purple wires -- Since i have not changed any wires ,are you thinking it may be the horn relay. I had the relay off this AM- tapped a few times with the butt of a screwdriver no change Is there a method of checking for extra grounds other than visual
 
I'm not sure how to interpret this, but disconnect the purple/black wire from the relay and see if the horn stops blowing.
 
If it's blowing when you removed the purple/yellow then someone has changed the way the horns are powered.
If you have a test light or meter, see if the spade C1 on the relay (the one that is supposed to hold the P/Y wire) has voltage when the W2 spade (purple/black wire) is grounded with a jumper wire to a known good ground.
 
Ok i was in the wrong box all along I have two small boxes atop each other This box has 9 you call spades (other has five) With my test light i found the spade which was live and feeding the fuse panel. (I have a great multitude of brittle wires) Shouldn't this be dead until the circuit is closed at the horn button
 
Only the horn relay has purple wires. The starter relay doesn't have any purple wires.
If you think you've found the horn relay, try what I suggested in post #9
 
Ok--disconnected the purple and black from the small five pin box no difference ,disconnected every wire from box still have horn The large brown wire from the top box (9 pin) shuts the horn off According to the Haynes manual the 4way flashers are on the same circuit and the Headlight flasher circuit ,not sure what that is The four ways and the horn are stopped I will look further to-morrow to determine if any other circuits are dead
 
Thanks for the link-they are easier to read--it would be easier if their were pictures of actual Circuits in the car . I know the ignition system was spliced in with an interesting blend of add on coloured wires etc Best to unwrap the harness to where the add on is spliced
 
A recent experience had my horn honking on turning of my wheel. I found a grounding strap at the coupling on my steering was shorting and making the horn honk. I am not sure if this could be your problem, but it sounds awfully familiar to me. If it is the grounding strap shorting at this location, it could mean your steering coupling is going bad, as mine did. If that coupling fails, so does your steering. Just sharing my experience, for what it's worth. I will be working on my horn as well. My car is a '74 TR6 and pretty original in many/most respects. If there is something you wish me to look at to help you, let me know. I am a shade tree mechanic lacking the sophistication of our well respected members on line, but have a desire to bring something to offer, when I can.
 
2Wrench--appreciate the offer. All I know is what I read in the manuals and what I am given on this site . I have been messin with this so much I have broken one of the spades off the box above the horn relay. So I must source another ,which is good as I get to stand back and think about it
The ground you are talking about is at the knuckle ?
Terry
 
Here is a picture of the "knuckle" or coupling. My horn honking was intermittent, as I turned my wheel. But in keeping with the idea that if your horn honks, it is because there is a ground somewhere along with you asking about other possible grounding points, I thought I would share. Here is the location in this photo. I haven't actually gotten my eyes on the grounding strap of which I speak. I am told it is attached somehow to the coupling. My coupling is on order. When I take the car apart, I expect to better understand exactly how and where the ground strap attaches. See the coupling pointed to by the arrow in the photo below. Double click to make it larger.

Coupling.jpg
 
The entire steering column acts one big ground wire so to speak when the horn button is depressed, but the rubber coupling interrupts the ground connection, so a woven flexible wire is run thru the center of the rubber coupling and connects to the steering column's flanges under the bolts on both sides of the coupling thus reestablishing the path to ground.
 
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