My 92 Fd is due it's 2 yearly check we have here in Ireland known as the nct test,and it's next monday..If you don't pass it you get constant hassle from the cops It's a basic check of light being balanced,suspension,tyres/wheels,brakes,wipers,windows and of course,emissions which rotaries are exempt from Here's my problem,I had the car apart and now I can't get the horn to work?I've changed the horn unit and horn relays and still not a peep and I know it's only something small.I'm operating a new momo wheel and have an earth and a horn feed and at the horn unit I have the feed and it screwed to the body.I don't know where to go from here .Can anyone lend me a few tips that might help me fix this???
Thanks guys.

 

The Body Electric manual in the stickies has a whole hose of electrical diagnostic procedures. I'd look through that first.

 

Get a multimeter and start checking around. You'll narrow it down along with the use of the body electrical manual mentioned above.

 

Just had a look at it there.Have a couple of ideas and was onto the mate there and he's gonna hook it up to his diagnostics tomorrow so i'll keep posted.

 

In the Diagnostic Connector, there is a "TAB" terminal. It is tapped into the horn signal wire which runs to the steering wheel and also to the horn relay. If you momentarily ground that terminal, i.e. momentarily jumper the "TAB" terminal to a "GND" terminal in the connector, the horn should blow with ignition either OFF or ON. If that works, the problem is between the diagnostic connector and the steering wheel connections. If it doesn't work, the problem is with the horn relay or the horn itself.