Help, I've NOT Got The Horn

My horn isn't working although it used to. I've checked the fuse, it's ok I've checked the horn & its ok. Took the horn cover off the steering wheel & there are two wires. The marks on the steering wheel shows a + at one & a - at the other. I was thinking about just running two wires from the battery to get it going but I'm unsure if they are positive & negative as I though it was just a straight forward earth when the horn was pushed as it looks like all that happens is that both contacts touch so I'm unsure if they are live & earth. I did run a live up to it & it did work when I touched one of the wires but there was a noticable clicking coming from the fusebox, possibly a relay? Any help?

ur horn is earthed to ur steering rack, if this has broken (witch they always do)
it is under the bonnet near the nuckle where the colom meets the rack,
hope this helps

Checked the earth where foxymk1 said it was, & it's okay there. Any other ideas?

Bridge the brass spring bit that rubs onto the back of the steering wheel to the metal plate thats screwed around it or any other earthed bit, door locking pins  for instance with a peice of wire and the horn should go off (make sure the ignition is turned on). My earth looked fine on the steering had it on and off and lost skin in the process but it still would not work so I earth that brass bit and off she went.

             Cheers Stu

Tried above post but still nothing. I've not got a clue. It was working then just stopped??

OK, process of elimination.

Firstly check your fuses. All of them, not just the one you presume is supposed to be the horn.

Only carry on with this if you have some basic electrical knowledge, and the idea of taking voltage readings from circuits doesn't make you anxious. If it does, then possibly best get an auto electrican in.    

<<edit>> First and a halfly, get a multimeter or voltmeter, pretty much essential to start looking at electrical faults. Pick one up for under ?10 easily. <<edit>>

2. Test the actual horn by connecting it briefly directly to your battery. If it sounded, then good, the horn definitely works. If not, then this is your problem. Get a new horn! (I know you already said it worked, but just double check!)

3. Test the circuit in the car up to the relay. To do this, turn ignition on and press the horn switch. Relay click? then good, the circuit in the car is OK. Relay not click? Could be a faulty relay or a faulty switch. To test, remove relay and put a voltmeter between the terminals that I think are labelled 85 and 86 on the relay and see if you get a good 12-13v when the switch is pressed.

Yes, then it's probably the relay at fault. No and it's probably the steering wheel switch or an earthing problem with the steering collumn. Test the earth on the steering collumn by checking the voltage between the metal part of the steering collumn and a +ve source such as the cigarette lighter (carefully!)

4. Relay click, but still no horn??  In this case, check the voltage at the horn while the switch is pressed. Anything much different to your voltage across the battery, and there's probably not enough to sound the horn (they need quite a lot of power) This could be the relay again (corroded or worn terminals inside or a faulty relay) so try a new relay, they're quite cheap to buy. It could also be the wiring or fusebox. If there's no voltage at all, this could be the relay, wiring, fusebox or firstly check the fuse again if there's no voltage at all!

5. If you have a low voltage, then test for current loss in both the +ve and the -ve circuit. For the +ve, check the voltage between the +ve feed on the horn and the battery earth while the ignition is on (they are switched by earth, the +ve is live all the time the ignition is on) any thing much different to the reading across the battery, and you're loosing current flow via the+ve side of the circuit (due to corrosion or degradion in the wiring or fusebox componants most probably.)

6. Test the earth by taking a reading between the earth wire for the horn and the battery +ve (while the switch is pressed and ignition on-so the relay is active!) and compare this to the reading across the battery. Anything much different. and you're loosing power in the -ve circuit (due to degraded wiring, fusebox componants, earthing point or the relay possibly.)  If you're getting good readings voltage wise, but it's still not working, then it might be a matter of ampage as oppose to voltage, (although voltage is a good indicator if there is a problem, high ampage is more of a stress, and some circuits only show up their problems under stress)

At this point, I'd be looking at the voltage and ampage at the horn end of the circuit while the horn is connected and being sounded, but hopefully by this point you'll have a working horn.    or maybe    let me know how you get on, and please feel free to say if my instructions are poor or confusing.

Mike.

I've not got the horn either and have tested the column and it isn't earthed.  How do I get to the knuckle to check the earth connection? cant seem to see a way in from under the bonnet or under the car? which is easiest??

Just to clarify, I can see the brown earth wire, its intact, just cant get to it.
There's no continuity to earth from the steering wheel but when a temporary earth is made the horn works fine.

Is this a new Clipper feature!?

I've not got a horn either but someone has previously bypassed it with a naff switch on the dash!

Will look into mine this weekend too - thanks for all the info guys!

Afternoon all, digging up this ancient thread as I've got a similar issue.
I've tested the horn connected directly to battery- ok
I've tested the relay by connecting it to the battery- ok (clicks as it should)
There is NO click from the relay when the horn is pressed on the steering wheel
Put multimeter across pins 85 and 86 in fuse board and 0v when horn is pressed
(Def the issue)
Checked steering wheel earth by measuring V between +'ve from cig lighter and steering wheel column, got a steady 12v

So, guess I'm looking for whatever 'feeds' pins 85 and 86 of fuse board and then trace back to find fault?
Looks like someone has been here before also, the wiring is a bit of a mess

Gonna take passenger seat out so I can fit in the foot well, been yoga posing to examine the wiring so far and its killing me

Wish me luck

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davidturner01 said

Afternoon all, digging up this ancient thread as I've got a similar issue.
I've tested the horn connected directly to battery- ok
I've tested the relay by connecting it to the battery- ok (clicks as it should)
There is NO click from the relay when the horn is pressed on the steering wheel
Put multimeter across pins 85 and 86 in fuse board and 0v when horn is pressed
(Def the issue)
Checked steering wheel earth by measuring V between +'ve from cig lighter and steering wheel column, got a steady 12v

So, guess I'm looking for whatever 'feeds' pins 85 and 86 of fuse board and then trace back to find fault?
Looks like someone has been here before also, the wiring is a bit of a mess

Gonna take passenger seat out so I can fit in the foot well, been yoga posing to examine the wiring so far and its killing me

Wish me luck

Sent from my SM-G950F using Tapatalk

Ok, gonna kick myself square in the nuts later for this
Turns out when I replaced the steering wheel I hadnt checked the brass ring had good contact with the small brass contact arm coming from the steering column
After very nearly tearing apart my electrics and fuse panel I noticed there was a gap
Bent the plate up a bit so it it was in constant contact with the back of the steering wheel, horn worked
Dont tell my Wife!!!
Hope this helps someone

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