Sportline Horn Poorly

I tried the horn on my 1991 Sportline for the first time today and could barely hear it.  It certainly didn't seem like it was firing both tones, but it was barely audible.  Any suggestions to look at?  Thanks.

Bad earth or dirty connections to the horn

Give it a clean up first and then run live and earth direct to test

Will give that a try, thanks.

chek the horn relay too, make sure it clicks when button is pressed

rubjonny said

chek the horn relay too, make sure it clicks when button is pressed

Is that on the fuseboard under the passenger side of the dash?  I don't have an owner's manual so not sure if there are other bits located elsewhere.

Well it is on mine but then I do have a LHD! 
All joking aside, I don't know if they relocated for RHD but I presume not.

Take a torch and have a feel around, you can't miss it. 

I remember having a BMW that had fuses under the dash, under the bonnet and the battery in the boot!  I am sure that the relay is above the fuses.

on the rhd cars its on the passenger side, its a 53 relay
http://www.clubgti.com/showthread.php?219775

Thanks Jonny!  Great link…I am guessing electrics is 'your thing'?

The relay by the way does click when the horn activates, so presumably rules that out.

Even if the relay is clicking, the contacts in the relay could not be making properly. If you have a multimeter you need to check at the horn that you are getting power there when you push the horn.

I've been known to dabble

try another 53 relay just to be sure, its a common relay used mk1/2/3 so you wont struggle to find a spare if you have a decent scrappy local. the yellow/black wire to the horns should have a good ignition live, the earth is whats switched by the horn relay.

make sure these wires are all buffed up shiny, if that doesnt help it could be the horns themselves. take em off and spray a good blast of penetratying oil down the trumpets and give it a good swish about then drain. plug in and see if they go off, if they do then get some kind of silicone spray down there to lube and refit. might be an idea to spray a quick blast while someone is parping them, get it all inside the workings. ear defenders may be a plan