Horn not working - pulling hair out help!

[milkman]

Hi folks,
I'm pulling my hair out over my non operational horn!
So far I have -

Checked for the usual airbag support frame mounting collapse - all ok
Replaced the horn which was faulty with an operating one
Checked the continuity of the clock spring which was fine but I've replaced it anyway!
Replaced the ignition switch
Replaced the horn fuse!
I'm at a loss any ideas?
Is there a relay on the rear bulkhead?

Any suggestions greatly appreciated as it's standing in the way of an mot!

 

[MisterCorn]

Follow the volts. Use a voltmeter to make sure you have power at all the points down the line from the fusebox to the horn.

MC

 

[deMort]

Wiring diagram is below ..

Basic system .. the horn button supplies an earth to the relay .. this actives a 12 volt to the horn .. each horn use the same feed and has a shared earth .

At the horns .. check for earth with a voltmeter on ohms setting (0 ohms to 1 ohm is fine ) .. ok ..

Check for a feed from the relay .. not ok .. check the relay has a switch earth from the switch .. term 85 , check you have a feed on term 86 ( 12 volts ).. if not check fuse B3 .. you follow it through until you find something missing ..

That will be a fuse or a broken wire if you have feed at one side but not the other on the wire .

Relay board 1 is above the fuse board .

Horn relay is in position 10 .

 

[milkman]

Thanks for taking the time to write that, amazing - much appreciated I'll go and have a look as soon as the rain stops!!!

 

[milkman]

Plot thickens!

Went out for a quick look admits the showers and in position 10 is the blue relay pic attached.

A quick google for a replacement shows this as the intermittent wiper relay!!!

Is this correct if so what type of relay / part number should be there!?

The car has been off the road since I acquired it and I've never tried the intermittent wiper setting so might explain this!!!

 

[Pip1968]

My only experience of this was replacing my steering wheel with a Cup one and the main issue with the horn was alll related to the earthing to make the circuit complete.

I would look at this aspect. A crocodile clip to a good earth point will see if this is the issue.

Once my steering wheel was all bolted down the earth connection was complete and it worked.

Pip

 

[deMort]

Relay board and positions 10 and 16 are next to each other .. you might have pulled the wrong relay out .

I need a model year of your car to confirm if every model year has the same board but i suspect it does... my instructions are based on a 2002 model year .

Horn relay is a bog standard 4 pin relay .

 

[milkman]

Fixed!
So a genuine thanks to all the help and comments!
I think sometimes when you've been at something a while you start to miss the obvious.
In this case the wrong relay in position 10 was the culprit.
Thanks again for all the help fixing this.

 

[qdunrpvcxsty]

It's been a while since your post, but I wanted to offer some insight. I'm glad to hear you finally figured out the issue with your horn! It's funny how sometimes the solution can be right in front of us, but we overlook it. Kudos to everyone who pitched in to help!

 

[qdunrpvcxsty]

It's been a while since your post, but I wanted to offer some insight. I'm glad to hear you finally figured out the issue with your horn! It's funny how sometimes the solution can be right in front of us, but we overlook it. Kudos to everyone who pitched in to help!

By the way, if you're ever in the market for an upgrade or just want to check out some cool horn options, you might want to take a peek at this Ryobi train horn on https://bosshorn.com/products/ryobi-train-horn-quad. It could add some serious flair to your ride!