[les g]

easy one Andy
you can check your switch with a meter to see when or what pressure the lights are illuminating
if you want the lights to be instantaneous you will need to find a way of fitting a mechanical pedal switch
some of our plant is fitted with these hydraulic b/l switches and you have to give the the pedal a hefty shove to get the lights on
the ones with mechanical switches light faster
it takes quite a bit of hydrulic pressure to overcome the spring inside the switch
also it can help if you mount the switch upside down or on its side so no air is trapped in the switch
it can be the air compressing and not lifting the switch/spring thing
cheers les g