That was the fault with mine "low fuel signal" when the dealer code read it so I would think its along the same lines.
I find its worth having a talk with the mechanic they can really put you in the picture especially if you are handy with the spanners.
But I would just take it in cause its under warranty & their problem.
As for the klr its great my mate has a 650 & he loves it too bits to be honest I bought it in august & ive done more miles on it than tigger
But it does the muddy slippy rocky stuff really well but can lack a bit of poke on occasions so Im looking to see what happens with trail riding over here then I may swap it ofr a dr400Z or a klx350 xr400 or something like that or if the uppity useless stupid government of ours ban it then Ill compliment the tigger & klr with a nice cruiser for the summer.