That's insane! Those are two separate systems as far as I know. I would try to find something common electrically to the two.... which would be hard since they probably just terminate at the fuse box.
One thing off the top of my head possibly worth mentioning is that the 55v power supply for the DIC's display lighting is inside the dash cluster. So if the cluster goes out, the DIC usually goes with it. So what's common to both the cluster and the cooling fans? :hmm:
I'll have to ponder this one for a while.