120 horn replacement

[karl2000]

Maybe youve got a bad earth - try earthing it to the battery directly. Astra is a 12v car i assume so unless theres massive voltage drop on the LC horn circuit (which i doubt) the different voltage thing doesnt make sense to me....

 

[Tractionman]

Astra horn fuse 15 amp ?

 

[karl2000]

BANG!

 

[Tractionman]

Not again !! lol

I had a quick Gargle, and although year and model Astra unknown, 15 amp seems general

 

[tony rodaway]

Maybe youve got a bad earth - try earthing it to the battery directly. Astra is a 12v car i assume so unless theres massive voltage drop on the LC horn circuit (which i doubt) the different voltage thing doesnt make sense to me....

Put the astra horn directly on to the battery and works perfectly and has the high pitch I wanted.

 

[tony rodaway]

Hello guys
Had a chance to have a go at getting the new horn to work via a 40amp relay.
I have the positive and negative connections plus another two connections going to the positive and negative on the horn plus a positive running from the horn to the oem wire loom and nothing no power.
Plan B
Bolted the astra horn to the body were the oem horn sits for extra earth .
No power even tho was connected to a relay and direct feed to the battery.
The astra horn has a positive and negative and so I tried to connect the + directly to the battery and jump on to the + on the relay and the - onto the relay and still no horn .
Just to check no fuses had blown I reconnected my oem horn and works perfect.
By this stage I had run out of ideas apart from going directly to the horn fuse and back to the relay I gave up.
Puzzled.

 

[karl2000]

Hi Tony any chance of a diagram showing what you've connected and where the relay is sitting? Its all a bit hard to follow as text!

 

[Tractionman]

Agree, it would help if we knew where you conmected wires on 4 pin ? relay

 

[tony rodaway]

The + and - as shown and put the spare prongs onto the + and - on the horn then run a connection from the + on the horn to oem harness.
I also switched the connections on the relay either way round to see if I could get power.
The only differencei did was i put my +from the horn to the double wire side on the oem harness.
I mention this because I followed instructions from a clip I found.
.

 

[tony rodaway]

Years ago, I changed the horns on my 78 as they were feeble. I had a high and low tone from a Fiesta, and although both horns worked off the battery, could never get them to work wired to the 78.
Like you Tony, I tried all sorts of combinations.My thoughts were at the time, the negative wiring on Toyota's ( dont know what the Fiesta's were), or they needed a relay, I gave up and left originals. Let's see where this goes.

Well traction man just like you I have tried every combination to get the astra horn to work with no results.
The horn works perfectly directly from the battery.
I have connected to a relay and via the battery via the oem loom and no power.
I have even run via the relay and directly to the horn fuse and again no power.
So like you I have give up as no idea how to connect and get power.

 

[Tractionman]

Hi Tony, looking at your pic and description of what you have tried, something is nagging at me, but I can't put my finger on it - mulling it over.
It is puzzling with the set up, as I found some years ago, and I gave up before you.
Hopefully, Karl will be on to clarify with his electrickery hat on.

 

[karl2000]

Hi Tony, is it wired like this, or some other way?

 

[karl2000]

Ever get any further with this Tony?

 

[tony rodaway]

Ever get any further with this Tony?

No drawn a blank as run out of ideas.
Even the relay option doesn't work so left for the time being but thanks for asking anyway Karl.

 

[tony rodaway]

Looking at your drawing Karl I never tried that way but has that method worked for anyone else or am the guinea pig.

 

[karl2000]

Well i dont know how else you'd do it that would make sense!

 

[karl2000]

If you get 5 mins draw out the way you tried and post that lets have a look

 

[tony rodaway]

Just followed your diagram Karl and bingo it worked.
Not sure how I wired it up the first time and second time but your diagram worked.
Big thank you Karl as saved me a headache.

 

[tony rodaway]

Years ago, I changed the horns on my 78 as they were feeble. I had a high and low tone from a Fiesta, and although both horns worked off the battery, could never get them to work wired to the 78.
Like you Tony, I tried all sorts of combinations.My thoughts were at the time, the negative wiring on Toyota's ( dont know what the Fiesta's were), or they needed a relay, I gave up and left originals. Let's see where this goes.

I followed Karl's diagram on page 2 and the astra horn works perfectly from the oem horn harness.
The 2 plugs on the oem horn I connected the wire on the plug with the 2 wires so looking at your oem plug it's the one nearest the passenger headlight.
That was my first try so may work of any of them.
Good luck.

 

[Tractionman]

Always good to have a result and post it Tony, many dont bother, so we dont know what happened.
Well,done to Karl !