Horn not working need help before MOT

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viragmakwana
Learner Driver
Posts: 14
Joined: Tue Dec 29, 2020 2:17 am
Vehicle: NA6

Horn not working need help before MOT

Postby viragmakwana » Thu Mar 24, 2022 6:14 am

Ok heres what I know

Horns work i have tested them

Horn fuse is fine, brake lights work as well

No 12v coming to the horns from the wire

No sound from the relay when pressing the horn button, but have already swapped the relay for a working one

Horn button works as i have tested the resistance

No 12v from the wire connecting to the horn button in the first place where does this wire go and should it have 12v coming to it?

Thanks for the help in advance

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PaulF
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Joined: Fri Jan 28, 2011 5:55 pm
Vehicle: NA6
Location: Newcastle, NSW

Re: Horn not working need help before MOT

Postby PaulF » Thu Mar 24, 2022 7:52 am

The horn button shouldn't have 12V to it, it's a switched earth.

There should be 12V at the relay though. Have you checked for that?

viragmakwana
Learner Driver
Posts: 14
Joined: Tue Dec 29, 2020 2:17 am
Vehicle: NA6

Re: Horn not working need help before MOT

Postby viragmakwana » Thu Mar 24, 2022 8:15 am

Yeah i figured that out around 10 mins ago, my bad, so i have 12v from one of the big spades and when i jump both big spades together horn works.

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viragmakwana
Learner Driver
Posts: 14
Joined: Tue Dec 29, 2020 2:17 am
Vehicle: NA6

Re: Horn not working need help before MOT

Postby viragmakwana » Thu Mar 24, 2022 1:37 pm

PaulF wrote:The horn button shouldn't have 12V to it, it's a switched earth.

There should be 12V at the relay though. Have you checked for that?
Yeah i figured that out around 10 mins ago, my bad, so i have 12v from one of the big spades and when i jump both big spades together horn works.

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PaulF
Racing Driver
Posts: 1801
Joined: Fri Jan 28, 2011 5:55 pm
Vehicle: NA6
Location: Newcastle, NSW

Re: Horn not working need help before MOT

Postby PaulF » Fri Mar 25, 2022 7:47 am

If you ground the signal wire at the relay, does that work? Just run a wire from that pin down to an earth point on the chassis. If that doesn't work, then your issue is between the relay and the horn. If it does work, then your issue is between the horn button and the relay.

FWIW, the horn button on my NA didn't work when I got it and it was due to a bad connection in the steering column assembly. I just ran another signal wire through a cheap button switch to ground, mounted the button to my dash, and that got me through inspection - in fact, it's still my horn button now.


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