I believe the Original one says "Nissan" or has "SRS" airbag on it.
Anyway, the point being, that HICAS relies on many things, one of those being, the steering angle sensor in the OE steering wheel.
I have a MOMO one of some description, thusly after some time over 80km/h, HICAS light comes on.
There is about a half billion threads on this board about it (including how to get it to do diagnostics in some wierd freaky fashion) but the general thing is, if you see the light come on, its not working.
HICAS is a questionable feature anyway. Yes it does aid the driver in a little way - but if you know what it feels like to be at the edge of handling, HICAS apparently sort of blurs that feeling a little. Meaning that some drivers don't like it, others do.
I don't have it (aftermarket steering wheel) so eventually i'll get around to grabbing a set of lock bars, and pissing off the 20kg of dead weight.
Oh, and disconnecting that bastard led that always comes up.