My horn is not as loud as it should be and theres a DTC coming up pointing towards the Horn Relay.... Wheres it located, MOT next week and afraid they fail it for being too quiet

Thanks

Paul

Think it's f20 in the engine box beside the air filter somebody correct me if I'm wrong according to here anyways..

http://knigaproavto.ru/shemy/en/ford/focus/99-ford-focus-mk2-fuse-box-diagram-20042010.html

You could be losing some voltage somewhere in the circuit but I'd say it's unlikely to be the fuse or the contacts inside the relay although you could try unplugging each of them and taking a look to see if the contact pins and/or sockets are dirty. Unplugging and re-inserting a few times might help to clean off any dirt or oxide and a shot of contact cleaner spray (NOT WD40!) could help. You might have corroded connections somewhere, possibly at an earth. If you could get access to the connections at the horn itself it would be interesting to measure the voltage whilst it's operating. Alternatively the performance of the horn may just have deteriorated with age simply due to the way it works, with the constant breaking and making of contacts inside. Most usually have some form of adjustment that can be tweaked to restore the lost performance but I've never looked at any on Fords so don't know if they're adjustable.

Thanks will be looking at it today, will give it a go