Horn of Plenty (pain)

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Ecopod
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Horn of Plenty (pain)

Post by Ecopod »

Engine wiring - got there in the end
Radiator fan - took a while but kicking in both speeds nicely
Washer bottle - tricky but stripped steering wheel and cleaned/reshaped brass bit and now works
HORN - I'm about to beat the van to death with a clothes pole

Working through electrics (building van from boxes of bits but most cab wires in place to old style fuses) and horn has me stumped, it is wired via a relay. To make matters worse it appears original (so should be easy) and only has single yellow/black wire to and single brown wire from.

Initially when horn earth was earthed horn would sound non stop if ignition was on. Cleaned and re shaped all wires/connectors etc and no change. Checked all earths (bottom of steering column/crown) and no change. Pulled relay wires apart and rewired as per wiki / then as per various other diagrams / then using every permutation of wire connections possible. No change other than not working at all for some combinations.

As it is a live system where on the column can I check it is actually live, I checked the Ve+ on push button itself but no voltage with ignition on or off.

Sorry for rambling but neighbours/partner pretending not to be interested.

(off to see Hereditary tonight - it won't be nearly as terrifying as T25 wiring)
83 W/C 1.9 DF or DG
4 speed / twin slider bus
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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

Take as step back and think about the basics.

Take a look at the wiring diagram. There isn't a relay as standard. The horn is an ignition live feed with earth provided through the horn button. Black / yellow feed, brown/blue earth (but brown on Aircooled). Provide a wire from the earth terminal to an earth and if the horn sounds you know you have a good horn and feed to it.

In case you don't have a manual / wiring diagram. http://syncrosport.com/info/wiring/VW_T ... _SP_DG.pdf

Take it back to standard and life will be simple.
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Thanks for taking time to reply, I think I've got every manual that exists and not sure why but they're not helping today.

- fuse ten goes live with ignition on
- blue/brown wire from fuse ten back to horn button and it is now live with ignition on and not jumping/bridging over to Ve- terminal

- yellow/black to horn and brown back from horn / horn working great if wired directly

What I'm completely failing to grasp is...what takes the signal back from the horn button to horn if blue/brown wire is only connected to fuse as above
83 W/C 1.9 DF or DG
4 speed / twin slider bus
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Oldiebut goodie
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Re: Horn of Plenty (pain)

Post by Oldiebut goodie »

Basically, fuse to horn ► to horn switch ► to earth at bottom of steering column. (unless there is a relay added for some reason) I can't see what your wiring is doing though. :)
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Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Cheers OBG, just finished cup of tea and will head out to try again. there is/was a relay but happy to throw it as far away as I can (or at least in toolbox for later).

Ta muchely.
83 W/C 1.9 DF or DG
4 speed / twin slider bus
Never forget you're unique - just like everyone else

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

If yellow / black wire is live and earthing the brown wire causes the horn to sound then you have 12v feed to the horn, what you need is to complete the circuit by providing an earth through the horn button.

I can't see why the horn button would have a live connection from the fusebox, it should have the brown / brown & blue wire from the horn.I suspect bodgery, amateur or professional :)

I see that your van is was an '82 Aircooled but now with a 1.9 DG, so quite what the wiring is will be difficult to know. According to Bentley fuse 12 should power the horn, but of course that's a US loom. I don't have access to my Haynes at the moment.

Ecopod, can you upload a picture of the wiring diagram you think matches your van best ?

This should be an easy fix
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Firstly thanks for helping out.

Simple set up also didn't work despite getting live readings up to horn push.

It was an 82 air-cooled with early fuse box/relay set up but it goes without saying there have been mods to wiring.

When I first looked at horn the blue/brown wire was connected to another wire that went up the left side pillar to no idea where (but will have to investigate at some point). If I earthed the horn return to crown head horn sounded (with ignition on - not with it off). I've now put everything back as I found it except for wire going up pillar, the blue/brown wire is now sitting unconnected and guess what, horn still sounds when earthed!

I've chosen this diagram as although it is for double horn it is closest to how relay is wired. I obviously have a single brown wire returning from horn.

Image


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83 W/C 1.9 DF or DG
4 speed / twin slider bus
Never forget you're unique - just like everyone else

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

What model / year is that wiring diagram for - no good trying to fit a square peg in a round hole, you really need to look at a '82 Aircooled :)
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

If someone has added a two tone horn / replicated the wiring then the way it works is as follows:

Horn has permanent live from fuse 16, earth route is via the relay, terminal 87.

Horn button is also live, from fuse 15, but via a number of connections in the fusebox, C20, L1, L4, C15, B25. Push the horn button, that creates the earth, relay is energised and earth path is provided for the horn.

To check that earth path you need to do a continuity test from the earth connection at the horn to L2 on the fusebox. Make sure the T2 connector is good first.

All the above assumes the two tone horn wiring has been faithfully replicated. Someone may have done it very differently, but on similar principles, or not :roll:
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Now in my defence m'lud that was the one that I thought best matched my wiring what with the relay :D .

But take your point so it would be as per 61/10 as per your link which may be from Bentley?

Beggars can't really be choosers but I'd prefer to keep the relay if at all possible just in case it is required in the future. However as the day of reckoning (MOT) looms closer I'll take anything I can get.

I'm off out for some food & liquid recovery but back at it tomorrow morning.

Have a grand evening.

Cheers.
83 W/C 1.9 DF or DG
4 speed / twin slider bus
Never forget you're unique - just like everyone else

Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Ah I was too late in responding to earlier message - I'll get onto continuity tests etc tomorrow and report back.

Cheers.
83 W/C 1.9 DF or DG
4 speed / twin slider bus
Never forget you're unique - just like everyone else

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

The file I linked to is I believe official factory manual wiring diagrams. I have also looked at Bentley Aircooled, but that is for US market so could be different. Still don't have my Haynes with me at the moment, might do later tonight.

If you have a standard horn fitted ask yourself why do you want to keep the relay, there's no real saving in wire length and the only current load saving is through the horn pad. I haven't come across one of those burning out :D

Enjoy the refreshments :D
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

I've just picked up my Aircooled Haynes manual.

Fuse 12 should be the feed to the horn, the earth wire is brown, which goes to a single block connector behind the dash where the wire colour changes to brown / blue and then to the horn pad.

Make sure the place where the horn pad contacts are actually has continuity to earth
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

Ecopod
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Re: Horn of Plenty (pain)

Post by Ecopod »

Good morning,

Picked off a couple of easier jobs first to make sure I actually finished something today!

Stripped out all wires etc going up pillar, there were many. 12 volts from fuse (10 as it happens with ignition on) to Ve+ side of horn measured and good connection, Ve- side of horn has nothing, brown wire back from horn is now joined to blue/brown wire from horn push (good connection), what looks like a good connection to earth on steering column. Still nothing.

Does this leave only the steering connections as potential fault despite my claims of having checked/cleaned all these.

I'm going to do an easy job next like rebuilding the brake callipers.
83 W/C 1.9 DF or DG
4 speed / twin slider bus
Never forget you're unique - just like everyone else

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937carrera
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Re: Horn of Plenty (pain)

Post by 937carrera »

Which way have you decided to wire the horn, with or without relay, what you have described seems to be a combination of them both ?
1981 RHD 2.0 Aircooled Leisuredrive project, CU engine
1990 RHD 1.9 Auto Sleeper with DF/DG engine

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