I have an Elnagh Marlin motorhome on a Fiat Ducato chassis with a 1.9 turbo diesel. It was first registered in July 2000 and I want to purchase a workshop manual. I tried one of the electronic versions on CDROM, but that was a complete waste of time and money. Can anyone please advise where I may purchase a book version and which one is the correct one to buy.
Many thanks in anticipation.</SPAN>

Try this website--
http://www.russek-manuals.co.uk/Fiat/fiat.htm

i have the 2.0 litre HDI(jtd) russek manual and it annoys me that it does not have enough information about the electrics/electronics.
It seems outdated for my 2004.

Many thanks. I finally got a Russek manual but it doesn't give much electrical information. Any thoughts on finding a circuit diagram? I have a problem with the horn and the Russek manual doesn't even show the horn.

how many terminals are on the horn?

T14086 said:

how many terminals are on the horn?

Click to expand...

There are 2 terminals. One is live all the time.
Do you know if it goes through a relay or does it work by the horn push just earthing the the other wire?

Fiat Ducato Wiring Diagram

pic of horn

Re: Fiat Ducato Wiring Diagram

Hi Ron
Run a wire to chassis from wire that is not showing 12v. If horn sounds - horn is okay and you have poor contact on horn sw.
If a blub will light across horn terminals and horn doesn't sound it suggests failure of horn and horn push is okay.
If horn found faulty, take it off and try it across a battery. Sometimes a knock might get it to work or fiddle with adjuster screw if it has one.
Just checked on my '87 model - one is 'live' all time same as yours.
cheers
lwm

Re: Fiat Ducato Wiring Diagram

Hi,
Thanks for your reply. I have tried all that you say. The horn works if I earth the other terminal. The horn push is also ok and makes contact. So there is a break somewhere between the two but without a wiring diagram I don't know whether it it is connected via a relay or just a straight wire. Information in a computerised handbook I read suggested that on some models there was a relay. Any idea?

Ron.

So, you are thinking that the earth return depends on a relay operated by the horn push
Theoretically this wouldn't make sense as a horn doesn't take much current.
More things you can do:
1) Study the handbook/fuses for indication of such.
2) Check for continuity from the horn earth to the horn push sw and see what colour the wires are at either end.
and then of course:
3) Find your relay.
4) Check for continuity, not just across the contacts, but from the earth side of the horn push as the earth has to be good from here. The grounding point on my older model is tucked up near the driver's foot well - this could have become detached maybe?

Someone with a similar model to yours may be kind enough to disconnect their horn and see if they can hear the relay click when they press the horn and where the click comes from?
Otherwise I'm stumped, sorry.

lightweightmick said:

So, you are thinking that the earth return depends on a relay operated by the horn push
Theoretically this wouldn't make sense as a horn doesn't take much current.

Click to expand...

Not really mate, if its a steering wheel centre push with airbag then it has a clockspring which couldn't handle the current.

Well I can tell you that the horn push on mine doesn't earth down at the driver's foot well, 'cos I've just tried removing one at a time and pressing the horn. Worked every time. The earth wires are difficult to trace as they are all black on mine...
I would suggest you run a wire from one side of the horn push - one should sound the horn and the other should only sound the horn on pressing the horn push - this then is the faulty earth.
let us know how you get on Ron...

Ah, just caught the Mod's post... glad I've got an old 'un!
So now we wait to hear if you've got an airbag!
You still need to make sure one side of horn push has got earth otherwise relay won't work anyway - no flow, no go!
But it's expensive to start messing with airbags...

If you need a result for MOT I would suggest running a wire through bulkhead via a push sw to earth off to one side. As long as it works. This will avoid any flimsy springs too, though do remember to tell the tester where your new fancy horn push is!

horn wires are red/green-live & white/black-switched earth.

No relay in circuit.

Def. need to find the point where the horn push earths then

Many thanks to all you contributors.
The earth to the horn push is ok. So I guess it must be a break between the horn push and the horn.
I have tried to find a point where I can graft in a new wire from the horn push to the horn but Fiat seem to change colour codes. The wire in the horn push is orange and blue, but can I find an orange and blue wire coming out of the steering column collection of wires - no!
So other than putting in a completely new horn push and wiring somewhere I am stuffed.
If only I had a circuit diagram with wire colour codes, I might be able to solve the problem.
Can anyone help please???

Ron.

Hi Ron,
has the horn ever worked while you've owned the vehicle?

Hi Mick,
yes it worked ok not so long ago.

ronrumbol said:

Hi Mick,
yes it worked ok not so long ago.

Click to expand...

By the way it doesn't have an airbag.

ronrumbol said:

By the way it doesn't have an airbag.

Click to expand...

I have at last found the problem.
As a last resort I decided to take off the steering wheel to investigate where the wires went to. There are two brass contacts that slide on steering wheel (earth contact) and the other one which makes contact with a brass ring.
Neither were making contact which is a mystery. All I can think is that the plastic assembly, which contains the contacts as well as the indicator and light stalks, had somehow moved down. I simply cleaned the contacts and undid the clamp for the plastic assembly and moved it up.
I now have a horn. It actually sounds like the one on "Noddy" the childrens character but at least it now works.

Many thanks to all the contributors.

All the best,
Ron.