2002 abs light comes on and off

my brother owns a 2002 and the abs light comes on and off. It doesn't seem to to happen under any specific conditions just whenever. It stays on sometimes for a few sec's or even an hour or two sometimes if it's on when he shuts it down at night it's still on in the morning sometimes not.
Has anyone heard of any recalls or tsb's. We haven't been able to find anything.
We live in heavy deer country and he's had to use the abs alot, but never had any problem till now.

i assume it's still under waranty. make the dealer fix it. otherwise check the speed sensors for contamination and the sensors wiring conections