Morris Minor Owners Club

Hello Sarge

Is it the big bulbous (original style) horn? From memoy this has two twin bladed terminals, could both the purple and the purple\black be on the same terminal? If so that is your problem, if not and they are on separate terminals then it's almost certain the horn has a fault. You can open it up and have a look to see if there is anything obvious?

Alec

I'm concerned about your brown/black wire - because wires of different colours are NEVER to be joined - golden rule of wiring! Does the fuse blow even if the purple wire is not connected to the horn ? First check - is there 12 volts at the purple wire at the horn ? Test with meter or a test lamp. If you now earth the other terminal of the horn with a jumper lead - does the horn sound ? If so - now fit the purple/black wire - and at the other end (steering column surely?) earth that wire with a jumper lead - does it sound the horn ? If it all works up to here - then the problem is with this mystery brown/black connection, although I can't see how unless it somehow connects a power source to earth when you press the horn...... If it fails to work, or blows the fuse earlier on in this process - then the fault is with the horn.....

Please dont be tempted to wrap silver paper around a blown fuse !
it could seriously damage your wiring . Over riding the fuse could cause wires to overheat
and could cause a fire ! Get a packet of 13 amp mains plug top fuses from the diy to use
while fault finding.A cheap test meter is an invaluable aid also.

I would get the horn working from a seperate power lead before connecting to the loom,
12v one side , earth the other. Alec could be right, my horn has 4 terminals (2 pairs)
so it is possible to inadvertently connect live and earth together at the horn.
Happy fault finding.

First check that the horn is working by connecting it direct to the battery terminals and check that the fuses are ok.
The feed to the horn should be live all the time so check that you have one live feed to one of the horn terminals. This should be purple. Connect the other terminal direct to earth and the horn should work.
When you have finished waking up the neighbours re connect the original wire, purple/black, and check the horn push. If no luck remove horn push and earth the central wire in steering column.If that is live then the fault is the horn push,if not live then the fault is beween the horn and horn push.

Hello Mike,

it can't be a fault between the horn and the horn push, as making the circuit blows the fuse. The one query is this strange brown\black wire, as BMCE says. The simplest thing is to disconnect it and try again, if the fuse still blows it has to be at the horn, it is possible that the solenoid has burnt out without going to earth? This would then draw too much current.

Alec

As far as I can see from the diagram there is no brown/black wire in the circuit. If a wire has black in it then it is a wire from a live component to an earthed switch.

Hello Mike,

this wire is referred to earlier in the post, it's not really known where it is from and may be a discoloured purple\black. If this is connected elsewhere to a live source this could explain the fuse blowing?
With cars of this age rogue wiring is more than likely?

Alec

If the wires are plasic coated it should be possible to clean them. If a wire with black in it is connected to a live terminal then it will short out. If it is connected to earth or a switch which is connected to earth then the component should operate

Hello Mike,

exactly, that is as long as convention has been followed, which is not necessarily the way. If the wiring is correct and the fuse blows when operating the circuit then the likely hood is a faulty device or too small a fuse?

Alec

As far as I know - the only 'earthed switched' circuits are the interior lights, the wipers and the horn......

Those are the only switched circuits I can think of except if electric washers have been fitted and wired in to the wiper switch by swapping it for a light switch
You should have 2x35 amp fuses + 10 amp side light fuse. There is no single component which will blow that fuse unless there is a short. Which fuse is blowing, live or ignition?
Check if the brown/black is live with and without the ignition on. If wired correctly then it should not be live unless it is earthing a component which should then start working. If it is not live then the other end is either connected to a switch or disconnected.
It seems fairly obvious, I am trying to follow a logical sequence of events

Hello BMCE\Mike,

as we have had no feed back yet from Sarge on these points we're in the dark a bit? It should be simple to sort out?

Alec

Perhaps the lights have gone out.......

Hello BMCE,

"Perhaps the lights have gone out..."

Alec

Can we charge consultancy fees?

Sorry for not getting on board a bit quicker, but I've been out in the N Sea for a while and the internet access is not only limited time wise, but also sites are resticted, message boards especially.
I got my horn working in the end. Dead simple really - I had attached both purple and purple/black to spades on the same terminal. It was only when taking it off that I noticed the lower set of spade terminals Yellow card Sargent !
I took notes and pictures 18 months ago when I had my fire, sure in the knowledge that I'd forget something, but my notes on the horn simply said "front and back"..

Regarding silver foil and the fuse - I know it is dodgy, it was just for a few seconds while I tested another wiring combination, no new burning smells.

Not quite sure what I did with the brown and black issue (still not home to check !) but I am pretty sure I sent the "spare" to earth and everything worked.

MOT this Wednesday, so it will be interesting to see what has seized, perished, been nibbled at etc. Wing mirror fell off, so that's one job pre-MOT. The wife thought she'd received a Valentine's present this morning. Onthe phone she was quite excited about a delivery on 14th Feb, I told her to open it up as there was something shiney inside . .. she won't fit my new wing mirror . . . . or cook me tea !

That is that problem sorted. it is usually the bleedin' obvious that causes the grief.
You can spend hours trying to describe symptoms and a fresh pair of eyes can spot the problem almost straight away.
Let us know how the MOT goes and if you are still cooking your own tea

I would have thought in North Sea you would get unlimited internet - to keep you happy! Good luck with the MOT.

Hello Sarge,

glad you found it, but I did suggest that very thing ten days ago?

Alec

Haven't got round to the MOT as I found oil on the rear offside brakes. Not a leak of fluid, but from along the axle.
The gasket is a bit battered, so I added a home made one and it seems to have done the trick.
A short test drive and the brakes are sharp and no leaks, but before I got to booking the MOT, the bloomin' left indicator has started playing up - side light flashes instead of flasher bulb. Also makes the right side main beam dim when LH indicator is operated. So re-check all earths again. Back to Aberdeen on Sunday, so the next installment will be some a while.

Opened up the dash to check wires there, so here's how I connected the wires from the steering column to the new loom.

All colours from steering matched to same colours on loom , EXCEPT :
Brown-Black from steering rack, which now goes to Purple-Black on the loom.

Black to black to loom to earth.

more fault finding to be done.