[Corsa D 2006-2014] Loss of horn

[Tigerfeet]

Just got a 1.2 58 plate a couple of months back with ultra low mileage. At first the horn was intermittent but now chucked it all together with the MOT coming up ! Had a look in the fuse box, fuse OK , checked out the relay, proved to operate OK and swapped it over with the Hi beam relay, still no joy. I have fed 12v down the wire to the horns from the relay socket and horns sound OK. I popped out the steering wheel Air Bag and the (3) horn push buttons are fine, of the two wires that connect ( blk+wh, br+wh if memory serves me correct ) one of which I presume is the coil feed to the relay and I got best part of a Meg Ohm resistance between the steering wheel and the relay socket !
I am assuming that the fault may lay in the steering wheel module, again I am assuming that the slip ring contact may have oxidised due in part to having only done 1.7k miles in six years . Does this sound plausible ? is it a servicable item or what is the cost liable to be new (gulp ! )
Any wiz kids out there who can offer any advice would be most wellcome to a returning Vauxhall fan

[walksall]

Welcome to the Forum.
I would have thought that the wiring colour to/from the horn switch would be: Brown (earth) and Brown/Yellow (maybe Brown/White?).
One Meg sounds a bit high but it does include the coil resistance of the relay.

Did you try earthing the switch wire directly to a GOOD known earth?

Regards

[Tigerfeet]

No I didn't simply because I had the battery disconnected at the time to pull out the airbag. In hind sight I could have checked more as per your suggestion. Although busy with work as I said the MOT was screaming up so I jury rigged a supply down to the horns with a local switch thru a relay fused off the battery. That took the heat off with a passed MOT ! A few weeks later I took another look and removed all the facia around and under the steering wheel to expose the Switch Module hoping to see a broken wire or similar, no joy, pulled a few plugs and sprayed them with switch cleaner and boxed back up. Later on I checked the relay contacts down in the fuse box and bingo !, connected my horn back into the original wires and toot ttoot !. Sadly it did not last ( don't you just hate intermittent faults ). I still suspect the switch module as I am assuming the horn wires go through some sort of slip ring arrangement ???........anyone ???

[Samo]

Do you have CD player controls on your steering wheel? If so, Do these work?

There is a common problem with horn/ stereo controls failing in the corsa D, unfortunately if thats your issue, its a dash loom replacement to fix it im afraid

[Tigerfeet]

Hi Samo , yep this car has stuff on the steering wheel spokes, I have only used the buttons on the RH side to control the radio volume and swap station all of which function fine , dunno about the Cd but will be checking tomorrow thats for sure.

[Tigerfeet]

Yep Samo, checked the remote audio butons on the RH side spoke of the steering wheel, all work fine swapping disc tracks, volume etc etc. I think essentially I need to know what happens in the switch module ? the housing below the steering wheel where the horn connection goes through ??? anyone ?

[Rocksta]

I remember a recall for these a few years ago to do with a wiring problem. May be worth looking into?

Don't rule out the relay. I had a problem with an iveco switches were fine, horn was fine and the relay measured fine but after a few seconds of being plugged in it was getting warm and sticking.