Technical Fiat Multipla Horn & How To Test With Circuit Tester

[multiplani]

More problems with the good old Multipla....

So the horn has died...now me not having the slightest clue about auto electrics...I tried the easy option first...stopped by local halfords and bought a universal horn with same fitment.

Fitted it...no go...so its apparently not the horn itself.

Connections look good, corrosion free and no breakages etc.

So picked up a wee circuit tester (Gunsons LED Circuit Tester)...and this is where I am stuck...

Not having used one before and knowing little about auto electrics...and very little abou the Multipla itself (God I wish Haynes covered this car)...I'm not quite sure where to start checking and how exactly to check it.

I've had a quick read through a Haynes electrical manual but to be honest I could do with a little straight forward advice from anyone who may know their stuff.

So can anybody offer up some advice for an electrical novice?

I'd really appreciate if anyone could spare a few minutes to give me a few pointers.

Thanks

 

[MrMultipla]

There is this thread you could have a look at.
Best to check the fuse first, sorry don't know which one it is off-hand.
Try connecting your old horn (and the new one) directly to 12v battery to make sure they actually do work.

 

[multiplani]

Yes, sorry...forgot to mention...fuse was another immediate first check.

What way would I go about connecting the horn direct to battery? Sorry but I'm pretty much a novice with the electrical side of things...was always 'afraid' of this side of things because dont understand it. I'm only getting stuck in now simply as the money is not there to pay the going rate for local sparks to start looking into it (£20ph)....and I have the time on my hands at the minute due to being off injured, so I might as well start learning how to do as much as possible myself.

 

[multiplani]

Oh, and thanks for the link...gonna check it out now.

 

[multiplani]

Yeah, useful link you gave me...anything I should be aware off before taking the airbag off to check the connections on one of these cars?

 

[momoe]

Assuming you're happy the fuse is ok, I'd check the relay first - if you're getting 12v at the relay when the steering wheel boss is pushed then it's not the steering wheel.
You can take the relay out and check that it works, i.e. apply 12v to the actuating contacts and you should feel the solenoid click. If you then check resistance across the switched horn circuit you should see the resistance drop to around 10 when it's actuated.
IF the relay is working then check the horn for current, it might be the horn is getting current and the earth is buggered.