Pre-Facelift Horn stopped working...

[TheWolfman]

So whilst annoyingly trying to beep at my friend and give her a fright I disappointingly noticed my horn had stopped working... which is hard for a man to take!

Relay seems good and is clicking away.Question is does a Pre-Facelift have two horns?Would be odd if both crapped out simultaneously...if it does have two I'm thinking it must be a grounding issue?

[Gavla]

Is it a sport steering wheel?

If so pop the BMW badge (horn press) out and make sure both wires are in contact on the centre piece.

To double check the horn, remove the steering wheel, there is a spring loaded carbon pin that contacts the back of the steering wheel. if you take a screwdriver and make contact with this pin and the steering hub the horn should sound.

[TheWolfman]

No,not a sports wheel....an original 4 button wheel.I don't think the steering wheel is the issue though as I can hear the relay click when I push the horn buttons

[TheWolfman]

So I can confirm that Pre-Facelifts do indeed also have two horns.I'm a bit baffled here because as I say the Relay clicks without problem when the horn buttons are pressed but I get no 'honk'! It would be strange that both Horns would pack up at the same time,I tried wiggling the connections on both horns whilst someone was pushing the buttons but no joy.They temporarily worked again the other day for a very short time so it seems like it's some kind of connection issue...any ideas?

Annoying that they're in such a pain in the ass location to work on...



[Contours]

In my car the carbon pin was not reaching the horn ring due to wear over many years. It would occasionally connect when I turned the wheel. I need a new carbon pin but to get through the Nct/Mot I managed to bulge the horn ring slightly so it make contact with the carbon pin. This has worked for some time so may be a temporary permanent fix.

[paultv]

If fuse 7 is failed or intermittent for one reason or another, the relay will still click, it may well click even if the contacts inside the relay are burnt out.

If you jump pin 30 and 87 on the relay base after pulling the relay out, you should frighten yourself to death with the noise - if none, is there 12v at pin 30??

Also check earth G104, on left hand front wing behind the headlight - best to open this up and give it a good clean anyway.

let us know!

Paul

[Brianmoooore]

If you jump pin 30 and 87 on the relay base after pulling the relay out, you should frighten yourself to death with the noise - if none, is there 12v at pin 30??

Also check earth G104, on left hand front wing behind the headlight - best to open theis up and give it a good clean anyway.

[TheWolfman]

Cheers Guys! Great info there, much appreciated.

Really should have thought about jumping that pin myself...

I will investigate as soon as I get a moment and keep you posted.

[TheWolfman]

So it looks like I'm getting +12 from pin 30 on the relay and across the Fuse when I short the relay pins.Also checked the ground point, all was good but gave it a clean anyway.I'm ascertaining the issue must be somewhere in the lead before the horns themselves.As it seems that both horns are affected it may be the loom connection in the fusebox maybe?

[Brianmoooore]

Pull off the plug to one of the horns and connect a 12 volt lamp to the plug with 30 and 87 linked on the relay base. Use a lamp of at least 21W (indicator or brake light bulb).

[TheWolfman]

So after getting somewhat distracted by trying to (unsucessfully..) sort out my high idle issue I got around to sorting the horny-horn out...

So after getting to the honky buggers it turns out all connections and electrics are good,I just attached multimeter to horn leads and saw +12v flash up when I pushed the horn button, both sides work.It was at this point I then realised that the reason for two horns is that they are actually at different pitches...one higher and one lower, it then became apparent why my horn always sounded somewhat ...erm.... 'clown-like'....I only ever had the high pitched one working! They were a pain in the balls to remove as they were proper seized on and can hardly fit a wrench in there,i found it easier to bend the bracket slightly and rotate the horn itself with ratchet on the bolt to loosen it up.

After rattling the high-pitched one around a bit I would get one 'honk' out of it then it would stop, so figuring it might be time for a new one I thought I had nothing lose by giving it a good couple of not-so-friendly whacks and spraying the bejesus out of the inside with contact cleaner... worked at treat! I know have one fully comedic horn back in action, and can happily beep a squeeky beep at passers-by until my replacement low-horn turns up and I can finally honk in unison....

Thanks for the help....BEEP BEEP!

The Horn with a good dose of anti-sieze after getting a good spanking for being naughty:

The leads:

[Stephenmoooore]

Well done for sorting it, but for future reference, connecting a meter to the leads proved very little. The current drawn by a meter is so small that the reading wouldn't be affected by a bad connection somewhere. Testing needs to be done with something that draws a significant current, like a lamp.

[TheWolfman]

Thanks Stephen, that's interesting.I am somewhat confused as to why a Meter wouldn't work though, if the meter is strapped across the connection where the Horn would be, it is reading whether there is +12 v going to ground, if a meter can't see that then that would be a serious problem.If no current would flow to an uninterrupted earth with basically zero resistance then that would indicate an issue surely?

[Stephenmoooore]

It's not Stephen, it's Brian. I've inherited my lad's old phone and it's still logged in to his account and I haven't a clue what my password is to change it.
At home I use a laptop but I'm currently sitting by the side of the river Loire in France typing this!

Modern meters are so sensitive that a series resistance of several thousand ohms will make very little difference to the reading, whereas just a few ohms would totally kill a horn.w

[TheWolfman]

Oh hello Brian!

The Loire valley eh? Very niiiiiice indeed!Beautiful place,I've been their before.....didn't have an E30 to drive over that amazing bridge there though then unfortunatly!That would have been fun.

Ahhh.. see what you're saying now, makes complete sense.Like I say I'm just going to have to doing more of a 'squeek' than a honk until my low-note horn turns up...

I'm pretty stuck on this High-Idle issue of mine at the moment, if you wouldn't mind having a look at my other thread I'd really appreciate it if you had any valuable knowledge to share on the matter, starting to go a bit 'round-the bend'