[SpookyZalost]

@tc4me glad that's been cleared up.

Honestly I think it's probably the iat sensor as that's what tells the fans to switch on and off and a faulty one would be triggering it so long as they have power.

Having an ignition control to prevent power draw when off is good but it doesn't solve the underlying cause, just prevents it from draining the batteries.
which is probably a good idea regardless since an idle vehicle with power draw is no good unless it's for an accessory plug to use stuff like an air pump or to briefly charge your phone.

It's why my always on accessory on my Jeep has a manual override to bypass the relay and go permanent positive when I need it but is ignition controlled when I don't, to prevent battery drain.

I'm surprised that feature isn't standard lol.