Hi, quick intro - on my 2nd Streetka - bought one new in 2004 & kept it 4 years before deciding I wanted something faster (kit car). Several yrs later my celica got written off last May by a drink driver & an eBay search of cars under £1200 within 50 miles saw me buy a Streetka (fond memories!) 

fortunately I knew what to look for & it's had all the major work done & most niggles were easy to fix - except the horn! I can't get it to work!

I've checked the fuse, and swapped it for good measure.

today I fitted a new horn, nothing. I assume it uses the earth just above, which I cleaned today.

now I'm getting a little stuck with no Haynes manual & not much info online - is there a relay for the horn? If so I assume it's one in the back of the fuse box - does anyone know which one? (And will a Halfords generic horn relay be worth a try?) 

i had a quick look at the steering wheel today to see if it was worth checking the horn wiring, but I got as far as disconnecting the battery and couldn't work out how to get the steering wheel cover off.

 

any help is really appreciated, booked in for an MOT next Saturday & only have Sunday's daylight left to sort it 

 

 

The horn stopped working on my mondeo years ago, turned out to be the clock spring unit in the steering wheel.  

If you've changed everything else this is the only thing I can think of, careful of the airbag though! I had mine done at the stealership to save worry from that particular little explosive, I bought the clock spring itself separately and they fitted it.

It's a mot failure if the horn doesn't work mind, just a heads up

Sounds like a simple case of electrical diagnostics.

In your case a broken wire / bad ground!

Did you check the continuity to ground by using a multimeter set for continuity/diode first?

You may have cleaned the earth bu that doesnt mean its actually earthed!

First thing is to get a cheap multimeter if you dont have one and check youtube if you dont know anything about electrical autmotive diagnostics.

Its not rocket science as so many people make out for simple items - it only gets tricky when you get into ccu/ecu stuff.

You really need to start from either the switch or the horn and work your way back / forward until you find the short.

I would first check for good ground then check the horn and switch hot points are actually getting a 12v as it may be the switch.