dual horn problem. One works on own but two wont

Hi everyone. Hoping someone can shed some light on this problem I am having.  

My dual horn only works when just one is connected when both are connected it just makes a bleep . 

Both are new horns . Any help would be greatly appreciated. Driving me barmy.  

Cheers mike 

I forget how the connections go bezy  but can you connect to each one individually and check they both work on their own (if that makes sense?)

Hi yes each one works on its own.  

Have you checked the horn relay? Useful thread here:
http://vwgolfmk1.org.uk/forum/index.php?page=topicview&id=electrics_2%2Fhorn-relay

This is often an earth issue or a low voltage issue

One alone will work fine but 2 would struggle

Check yourvearths are good and your getting a good healthy 12v to the live  

thankyou, i shall clean up the all the contacts. anyone know where the earth points are? cheers for your help. 

I had this problem, some times worked if engine was running but other times not. Ran just one horn for a few years. Only way I fixed it was to replace the two horns with new ones.

Pretty sure it's a voltage issue now. Anyone else had the same problem and overcome it? The horns are both new. 

Fixed it. ☺cleaned and replaced some of the contacts., the relay and Checked with multimeter and voltage was up. Horn now works a treat. 

Thanks to everyone for the help. 

Mike 

Nice one