Croc bait

Sorry, Hello, Yes the horn works but only when the engine is running.

Got an electrical gremlin in a DT175. when braking the headlight dims, when indicating the headlight flashes. indicators dont work at idol and dont work unless the bike is running. I thought it was a bad earth so I have cleaned all the earths and checked all the conections. Anyone got any ideas as to what i should try next?