Morris Minor Owners Club

Hi,

Looking for some advice. The horn on my 1964 Morris Traveller has stopped working. I had been having some electrical problems for a while (See other posts) that was eventually tracked down to a faulty break pressure switch. That was replaced and all my indicator, fuel gauge problems and blowing fuses issues were sorted.

The last week I noticed when out for a run that my horn was silent. I have the spoked steering wheel and removed the retaining screw that held the horn button on. Cleaned things up and I have even removed the steering wheel after following the excellent posts regarding the engineers hammer as the horn button had always been on squint. Replaced everything but still no horn.

I read one post that referred to the interior light also being linked to the horn. I have never had a working interior light even after me and my dad traced it all through and repaired melted wires a few years ago. I checked the wire for that and it seemed fine.

I then used a volt meter (no idea how it works) set it to 20 and attached the earth to the battery earth and the live to the horn and it read 3 (volts?). It also read 3 on the earth wire coming into the horn which suggests that power is getting to the horn.

Is there anything else I can check? Has the horn just died and I should replace?

Many thanks for any suggestions.

Cheers,
Scott.

Scott
Starting from your " no idea how it works " statement.
You need to "see" battery voltage on the Multi meter tests.
Start by the using the meter set to Voltage DC ( direct currect ) setting.Put the probes on the battery terminals, positive and negative.Record the battery voltage, e.g 12.6 volts.
A 3 volt reading is telling you something is wrong in the wiring ( the horn is probably working OK , see later test to check for ultimate test of this statement )
Follow the wiring diagram for your car.
At the horn itself , the purple wire "supplies " power to the horn....so it should be "battery voltage " seen on the meter, if all is well.
Connect the meter red wire probe/ clip to the purple wire female connector ( i.e. take the wire off the horn to make the test and then replace ).Meter black probe/ clip to the negative post of the battery.If you don't get battery voltage, you need to trace the wiring back until you do.Look for any damaged wiring back to the fuse box, clean the fuse connections, if necessary.
Are the male connections on the horn itself clean ?

Noting which wire is on which terminal, disconnect the purple and purple/ black wires from the horn.You can test that the horn works by temporarily attaching a wire from the positive battery terminal to the horn terminal that had the purple wire on it and a second wire from the negative battery terminal to the purple/ black terminal.As soon as you do this the horn will sound ( if it is working ! ) so make the connection briefly.Either wear ear defenders or be prepared to hit your head on the bonnet as the sound makes you jump !! If no sound then horn is duffReplace both wires and test with the horn push.....? Working now ?
If not then the "earth" side ( purple / black wire ) is suspect.
Look for the bullet connectors ( in a small black rubber housing 3/4 " ) before the wiring carries on ,in the short bit of loom up the steering column.They might need a good clean with sandpaper/ emery paper.Red probe/ clip to the bullet on the end of the purple /black wire and black probe/ clip to battery negative terminal ...does it see battery voltage ? Good.... replace connector in the housing.
Give that lot a go and let us know what you find.The problem may still be within the steering column but check everthing else first before removing steering wheel, etc.

Armed with your knowledge you can then check out the interior light saga.
The wiring diagram shows both wires ( both purple one interior Light and one horn supply ) come from the same fuse supply.
Physically remove the fuse from the fuse box, clean the holder and both ends of the fuse.A "quick look / glance " may not detect
the problem, cleanliness / good contacts for electrical efficiency is essential.Bullet connectors again before it disappears up the body work pillar right hand side of the windscreen.Remove the interior light, if power is OK, up to dashboard height bullet connectors.Test the purple supply wire again behind the light.If power OK.Is the bulb blown ?
If not, then it's the earth side.Black wire this time check, clean test , etc You should be getting the hang of this by now !!
Just be methodical, rather than jumping about from one area to another.Check supply first ...only 3 volts is the clue 25% of what it should be... then earth.
Good luck with it.
Bob

Check the purple wire to the horn, it should be live, if not check the fuse. The purple and brown wire should be live to the horn push and the horn should work when the wire is earthed.
Remove the wires from the horn and connect the horn directly to the battery, if it does not annoy the neighbours then you need a new horn.

Many thanks for this fantastic information. With a friend I managed to work out how my multi-meter worked and could see 12v going into lefthand side of the top fuse and only 0.04 going into the rights hand side. I replaced the fuse and hey presto 12v both sides.

With bated breath I tried the horn. Nothing Checked the fuse. Blown.

I will try out the great suggestions above and let you know if I find anything else.

Cheers,
Scott

If the fuse blew straight away it could be your interior light wiring that is blowing it as you have said the interior light doesn't work. Remove both purple wires from the fusebox, replace the fuse and then connect the thicker purple wire that goes to the horn. If the horn works you then need to find the fault on your interior light circuit.
Message me if you need a good clear colour wiring diagram.

The good clear diagram is at the head of this section! Scotty has been here before with the purple wires........ Take the purple wire off the horn - is the fuse ok now? Refit the purple wire. Then take the other wire off the horn -and now take a short length of wire, connect it to the horn (where the second wire came off...) and touch the end to earth - does the horn sound ?? If so - the horn is fine - if it blows the fuse (20 amps minimum I hope) then the horn is faulty. And if the horn doesn't sound - it's also faulty!!

Hi,

Eventually got back to this as my wife was focused on shopping and DIY this weekend so just managed to sneak back out to the garage and following all your excellent instructions.

Ok I can confirm its not the horn. Followed the instructions to connect a couple of wires and off it went. Luckily I was well prepared and did not hit my head of the bonnet My suspicions were now raised about the interior light and the fuse was replaced and when I opened the drivers door I decided to check the fuse before pressing the horn and it was blown. Wound the window down replaced the fuse and pressed the horn. Horn works. Fuse does not blow. Interior light guilty on 2 counts

So now I need to work out this damn interior light thing which has never worked (I have only had the car around 23 years ). I once did try and fix it and my dad and I tried to fix it but no luck. Recently when trying to sort out other electrical problems I noticed the brown wire going to the door switch had melted. I replaced it and it seems to be fine now. The passenger door switch needs to be replaced as it is jammed into the door post.

Any tips to trace the fault? Feeling vey professional now I (sort of) understand my multi-meter

Cheers,
Scott

I had this problem and it was the connections to the interior light. There are 3 wires on the light, power feed (purple) connected to one end of the light, a switched earth (black/brown) from door switches connected to the other end of the light (the door switches connect together on the dirvers side) and a permanent earth (black) connected to the switch on the light (so the light can be turned on when the doors are closed)
I had the purple connected to the switch on the light and the switch was on, so when the door was opened there is a direction connect from the power feed to earth and the fuse blows.

So check all the connections on the light and disconnect as necessary to determine the location of your problem

Thanks Andy,

Will check out the switch although I don't remember changing it in the past but maybe I did reconnect it incorrectly when car was originally restored.

I like your traveller looks same as mine.

Will let you know how I get on.

Cheers,

Scott

You mention brown wires going to the door switches. What year is your car? Later cars had purple/white to the door switches.
Disconnect the brown/black (or purple/white) at the interior light. Does the light operate with it's own switch or does it still blow the fuse?

Hi Beero,

It's a 1964. I need to check but I think it's one of those Dual-personality ones http://dpminors.wordpress.com/

I will check the wire colour again and let you know for sure.

Cheers,
Scott

Here is a picture of the interior light which looks correct to me. I noticed the door switch on the passenger side was broken so I have ordered a new one from Tom Roy which should come on Monday.[frame][/frame]

Hi, I dont think your wiring is correct

All the wires that supply earth, i,e via door switches and switch on light should be at the top on your picture.

In your setup the Black/Brown will be connected to the purple via the light switch the way it is currently wired giving a short and this will blow the fuse.

The purple live wire should be the only wire on one end of the light, i,e bottom left connection in your picture, I believe you need to swop the purple and black wires.

Hope this makes sense

Andy

Agree, swap the purple and black. That is probably what was blowing your fuse.

Ok thanks..I will give it a try. Once I get the new door switch I will reconnect and update you.

Many Thanks!
Scott

Hi,

Great news! All is now working. Sorry for the delay in posting back but the weather this last week has not been an encouragement to go out to a cold garage.

This is what I did. Fitted new door switch on the passenger side, tidied up the original wire and soldered a new piece of wire onto it. Connected that up and then turned my attention to the interior light. I swapped the wires as suggested in earlier posts. It was a real struggle to re-connect the purple wire to the opposite side of the interior light unit as there was no give in the length of the wire. Eventually I managed to connect all the wires as suggested.

Inserted a new fuse and viola! An interior light that is now working. I have had the car for about 20 years and this is the first time I have seen the interior light come on when you open either of the doors. Fab!

Many thanks yet again for all the help, hopefully that will be my electrics working fully for a good while after a number of problems, but the electrics hassle, while annoying has been worth it. I now know how to test a connection with an electric meter and a bit more about how the Morris is wired.

Below is a picture of "Oor Jessie" the cause of all the hassle..still looking good at 48 and a half. Now for new brake shoes front and back.



Cheers,
Scott.[frame][/frame]

Well done, you see, wiring is not that scary after all!

Well done, glad to see my understanding of your problem was correct and it helped with the solution.

Scott

Well done for persevering.As they say " a good learning experience " and " onto the next problem " !!
Bob