Hi - when I go on full beam horn comes on my scania. Anyone help!
Maybe the horn just really, really likes the full beam?
Offer it a cigarette,it’ll be fine
Are you near any wooded area car parks when this happens
It’s a warning and it means “outta my way I’m coming through”.
real answer … try a new stalk or look for chaffed cable near steering column…
Trukkertone:
real answer … try a new stalk or look for chaffed cable near steering column…
Thanks mate - nice to get sensible reply when you’ve been up since 2am. Thought about taking out fuse for horn until I can look into it further but it doesn’t tell me which one. Don’t suppose u know to save going thru them all
Ah! You’ve got a Light Horn. Nifty. 
If it’s an 8-wheel tipper they’re all like that 
Does pressing the horn silence it? That seems to be the way it is in Asia…
Volvo has a similar issue with full beam coming on when indicating. Micro switches on the printed circuit board at the base of the stalk is apparently the problem. If your full beam and horn are on the same stalk then that sounds like the same issue.