Install fog lights and give them the connection directly from head lights.
Install wiring that comes with fog lights.
but some times there will be pre installed wiring of fog lights in vitz like in mine but no fog lights.
never ever try to connect your fog lights with that wiring.
because i tried it and after installing fog lights with that wiring in my 2014 modle vitz bought in 2015 march .
I end up with ABS and CEL .and problem turn out to be damaged ABS unit .Then Definately replaced the ABS unit.