Morris Minor horn mystery

[jehuie]

Hi all,

I tried searching on here for this info first but couldn't find it. I'm working on the horn push on my Morris and having a hard time finding actual pictures, drawings or videos about how it all is supposed to work. Most of forum posts around the web were made many years ago and the links are all dead.

So here's the situation:

1) My car horn has been in a box that came with it ever since I've had it. I was waiting on a part for the engine so I thought I'd finally install it.
2) I tested the horn with alligator clips directly to the battery and it works fine.
3) i found the purple and purple/black wires laying in the engine compartment. They had been clipped off so I installed new bullet connectors and attached them to the horn.
4) I went into the car and pressed the horn push. Nothing happened.
5) I turned the key in the ignition and pushed it and then it suddenly went off but CONSTANTLY. Nothing would stop it, including turning off the ignition. So I went and unplugged one connector to kill the noise.
6) From then on, touching that wire to the connector would cause the horn to beep no matter what I did.
7) I took the horn push out entirely. The horn still beeps when I connect it.
8) I removed the steering wheel. The horn still beeps when connected.
9) I removed the turn-signal mechanism and finally the horn stopped when connected.
10) I put it back together and now no matter what I do, I can't get the horn to beep, other than direct connecting it.

Ideas?

I'll post a few pics in a bit.

 

[jehuie]

Here are some pics:

 

[jehuie]

Man those pics came out big. Anyway, I don't understand how the mechanism is supposed to even work. What is supposed to press where to make contact to blow the horn? It also doesn't help that I don't know the terminology for many of these parts.

I'm assuming that depressing the horn button is supposed to push down on that rubber piece with the spring around it. And then that is supposed to somehow make a piece of metal somewhere make contact with another piece of metal somewhere?

 

[DrEntropy]

The first obvious issue is that the circled "thingy" that is a copper alloy band-like part is bent out of position and SHOULD be sitting so the button on its end rides on the "band" (arrow pointing to it) on the shaft, rather than in direct contact with the shaft itself. I believe that's why the horns go off constantly.

 

[DrEntropy]

Solid green wire carries power to the turn signal portion of the switch, green/white for the right side signal's voltage out, green/red for the left. Someone was "creative" apparently and somehow added the light blue wires and that house-wiring speednut. Not sure what that's about.

The horns operate by grounding the purple/black side ordinarily. The straight purple wire should have 12V at the horns.

 

[DrEntropy]

I've no diagram for the Morris, not had a switch like that apart in decades and can't recall how it is supposed to be connected. I see a black wire in one photo, that should be a ground wire but not sure how it would be attached or to what. Someone else should see this soon and have better info. I ~think~ it should be connected inside the column to that "button" at the top end of the shaft.

 

[jehuie]

Thank you all. The combination of things you said helped me figure out how it is supposed to work. And the problem is pretty obvious now. It sure seems like there are a lot of contact points in this little circuit that can get messed up!

 

[jehuie]

One more thing....the light blue wires look like they go down the center of the shaft of the indicator switch arm. Mine has a light on the end that used to flash when I would turn them on. Which was kind of a cool little gimmicky thing. Is this not a stock feature in the Morris Minor? Looking at videos online it doesn't look like they had this light at the end of the arm. But maybe it was just certain years? In any case, it's not working now. And one of the blue wires is just dangling and not connected to anything. But it is not obvious where it should connect either.

So far, I have not been able to find a wiring diagram for this sucker.

 

[jehuie]

Ah...I think I have it figured out. Simple and obvious when you just look at it. Stand by!

 

[jehuie]

Ah...I think I have it figured out. Simple and obvious when you just look at it. Stand by!

Ok, I found the solution to the flashing light on the turn-signal issue. I probably should have put that part in a new thread but here we are.

I don't know if this is how it was originally or not but it seems to work for me. I believe each of the blue wires goes up the arm of the turn-signal to the same side of the bulb. While the other side of the bulb is grounded.

The pad between where I have soldered the blue wires is always hot with 12 volts. Moving the arm up or down on the shaft closes the switch which powers the flasher for signaling left when flipped one way, and right for the other.

So by soldering one blue wire to each of those pads it causes the light at the end of the arm to light up and flash at the same time as the outside lights.

At least it works for me!

Also, I cross-posted this on the Morris Minor forum in case it helps someone.

 

[DrEntropy]

Don't argue with success!!

Have you sorted the horn issue?

 

[jehuie]

Don't argue with success!!

Have you sorted the horn issue?

Well, someone on the Morris Minor forum is telling me that I did it wrong with the signal wiring so I'm looking into that.

For the horn, I think I understand how it's supposed to work now. But I have not yet assembled it to try to fix it since I'm futzing around with this signal thing.

 

[jehuie]

And they were right, of course. For future reference....one of the blue lines going to the bulb needs to go to that farthest away pad on the turn-signal mechanism. That goes to the P tab on the flasher unit and causes it to flash when either turn signal is on. The other blue wire goes to ground.

Also, check your grounds. that turned out to be why it stopped working in the first place. The ground wire went to a painted piece of metal under the dash. I sanded it down to give it a better ground and all is well! Also, I had a similar bad wiring issue with the horn.

But everything works now. Thank you for all your help!