MOT tomorrow and my horn doesnt work HELP!

[STU175 0]

hopefully someone can help?

 

the horns work when powered direct off battery...

 

i can hear the relay clicking ( does this mean its ok? ).....

 

checked where the wiring to horns looks fine.....

 

no voltage found at horn plugs using multimeter....

 

no earth found at horn plugs using multimeter.....

 

it worked last month.......

 

EDIT checked fuse....

 

EDIT i have checked and there is no 12v on horn connector using battery as earth...

 

EDIT have double checked slip ring all is good 12v & earth on wires that plug onto horn button....

 

 

any one point me in the right direction???

 

perhaps should have checked earlier :bonk:

Edited May 16, 2012 by STU175

[KIPVW 0]

I hate electrics, cant bloody see it. you checked the fuse?

[STU175 0]

I hate electrics, cant bloody see it. you checked the fuse?

 

yeah checked fuse forgot to put that, any other ideas other than one of these? LOL

 

[ATTACH=CONFIG]62489[/ATTACH]

[Jon_vr6 1]

I had this on my old steering wheel in that it didnt work when the steering wheel was straight but moved to either the 10 oclock or 2 oclock position and it worked fine, ending up swapping the steering wheel for a brand new refurbed one and noticed when i took the steering wheel off that there was a hell of a lot of build up of grease on the slip ring on the back of the steering wheel and on the little copper clip on the steering column worth a try fella also check under the horn button that the connectors are in ok condition

[STU175 0]

I had this on my old steering wheel in that it didnt work when the steering wheel was straight but moved to either the 10 oclock or 2 oclock position and it worked fine, ending up swapping the steering wheel for a brand new refurbed one and noticed when i took the steering wheel off that there was a hell of a lot of build up of grease on the slip ring on the back of the steering wheel and on the little copper clip on the steering column worth a try fella also check under the horn button that the connectors are in ok condition

 

did have a look at this but relay is clicking so presume that part is ok ??

thanks anyway mate:thumbleft:

[owen g60 10]

As you state there is no power to the horns when measuring across the pins when the button is pressed.

 

Check the voltage at each pin putting the negative probe on the battery negative terminal and pressing the horn.

 

If you get a voltage on one pin for each horn then the relay and circuit are ok.

 

You will have a broken earth wire somewhere.

 

Just run a wire from each negative pin on the horns and earth them anywhere on the chassis as an easy fix

[STU175 0]

As you state there is no power to the horns when measuring across the pins when the button is pressed.

 

Check the voltage at each pin putting the negative probe on the battery negative terminal and pressing the horn.

 

If you get a voltage on one pin for each horn then the relay and circuit are ok.

 

You will have a broken earth wire somewhere.

 

Just run a wire from each negative pin on the horns and earth them anywhere on the chassis as an easy fix

 

thanks for the reply ill check that tomorrow:thumbleft:

[Stonejag 10]

noticed when i took the steering wheel off that there was a hell of a lot of build up of grease on the slip ring on the back of the steering wheel and on the little copper clip on the steering column worth a try fella

If it's not a bad earth this would be my bet. Steering wheel off (gently pop the front cover away, undo 24mm nut underneath and pull) and give the whole slip ring a good clean with some meths or similar - also the brass ring on the back of the wheel. You can also GENTLY fold the small metal tab up slightly to contact the wheel a bit more firmly. While the wheel's off, short the pointy contact plate to the centre mounting nut with a bit of wire - if the horn sounds then the fault's in the wheel or slip rings, if not then probably earth. Small smear of vaseline / silicon grease and it should be good to go :)

 

Stone

[STU175 0]

right ok now i have checked and there is no 12v on horn connector using battery as earth...

 

have double checked slip ring all is good 12v & earth on wires that plug onto horn button....

 

what else could it be??????????????

 

HELP

[swiftkid 1]

I'm no electrician and I'm still very much learning electrics (self taught!!!) but I'll give this a go

 

So the relay is clicking? this means we know that the relay has an earth and power from the steering wheel. Have you tested that the wire from the relay to the horn is in 1 piece? Maybe get a long piece of wire from the relay and connect it directly to the horn. If that works you know you have a problem with the wire and you can use a multimeter to try find the problem. I don't know how often a horn brakes but have you connected a 12v feed direct to the horn?

[STU175 0]

I'm no electrician and I'm still very much learning electrics (self taught!!!) but I'll give this a go

 

So the relay is clicking? this means we know that the relay has an earth and power from the steering wheel. Have you tested that the wire from the relay to the horn is in 1 piece? Maybe get a long piece of wire from the relay and connect it directly to the horn. If that works you know you have a problem with the wire and you can use a multimeter to try find the problem. I don't know how often a horn brakes but have you connected a 12v feed direct to the horn?

 

thank for the reply looks like i have found the problem!

the loom runs from horns to a connector below headlight near intercooler only visable when you remove air duct off front of intercooler.

the wire seems broken as it enters even tho the insulation is fine????

 

well at least ive found it now....