The automatic triggering of my IC water spray on my JDM STi7 seems to have stopped. It works fine from the manual button and the light on the auto button does come on.

I no longer hear the relay trigger at 4000 rpm or thereabouts, so whatever triggers it has stopped working.

Any ideas what might cause this? - is there a separate fuse for this or is it more likely a relay is faulty?

Any help appreciated.

Is it not actuated at WOT ?
erm if so, could be a switch on the throttle pedal come loose / mis-aligned (perhaps it got kicked !!! )
only a suggestion as I don't KNOW how it's controlled