Howsit everyone.
So I have a 2015 s40 boulevard wanting to know what colour the wire is for low beam headlight.my problem is I use to be able to push plug underneath tank on the right side or wiggle cord and tape in place but now my dodgy fix is no longer working.what puzzles me is high beam still works which is a plus as I work night shift altho im sure the cagers are sicking of me frying there eyeballs. also running lights usually work aswell as horn.i looked at other wiring diagrams but the colours dont match mine so im stuck as to what wire in harness i should be checking for connection.i will admit im a complete noob when it  comes  to anything electrical.any advice would be much appreciated.
Cheers

The problem won't be in the connector under the tank, as the hi/lo beam split is in the left handlebar switch.
As Dave said, the wires going into the headlight bucket is a prime suspect place.  It could be the headlight bulb as well.