Odd issue with air horns

[Craig98sxr 0]

Hi all,

Not a big issue and still working on it but have just installed air horns [ eBay cheapies but heaps better than standard ] to work via the factory horn button and not sure if it's my wiring or the cheap relay but when I hooked up the factory cable to the relay for the air horns it operated fine 3 times then blew the 7.5 amp fuse under the bonnet no spares the right size so temporarily used a 15 amp fuse & now works fine but the relay is heating up and staying hot while the wiring is connected. Is there maybe a residual current in the factory wire? Now thinking try new Hella relay and if still an issue then a spring loaded switch on console or dash in one of the blanks I think.

Anyone have any idea's or experience to offer. Thanks in advance, have looked at a lot of internet stuff but couldn't find anything specific to our cars.

[marks_2_sparks 4]

Without knowing anymore information I think you need to check how you wired the relay. Sounds like you might have the relay constantly turned on and be powering the air horns with the factory horn wire. Was it the aftermarket fuse that blew or one in the fuse box? 

[Craig98sxr 0]

The one in the fuse box blew, I've rechecked the wiring but anythings possible, also its a cheap no name relay that came with the horns I'll keep on it over the next few days. Main power came in on pin 30, air horns power on pin 87, earth on pin 86 and horn button [ power when button pushed ] on pin 85. Any suggestions welcome Thanks Mark

[Craig98sxr 0]

Just closing this off. Bought and fitted a good quality 30 amp relay [ Tridon brand ] and all issues solved - works perfectly - no fuse problems and no heat in relay at all so cause must have been the cheapie relay that came with the kit, pity as the horns are really good.

Thanks for the interest and advice.