Queens prosecutors declined to file charges against the grandfather of a 3-year-old boy who went missing, the District Attornye's office said yesterday.

The boy, Kah-yon Reynolds, disappeared after his grandfather, Wiley Reynolds, 49, fell asleep on a Queens-bound F train Saturday. The boy was later found in Newark, where he lives, after he was taken home by another man who he knew, police said.

The older Reynolds last saw his grandson as the train passed the Smith and 9th Street station in Brooklyn. When he woke up in Queens he was gone, police said.

Reynolds was charged with failure to exercise control of a minor, but the charges were dropped, the DA said.