A 41-year-old man involved in a fender bender on a Bronx highway was fighting for his life Friday after he stepped out of his car and was struck by a passing minivan, cops said. The victim was heading east on the Bruckner Expressway approaching Castle Hill Ave. and the Whitestone Bridge about 3:45 a.m. when he got into a motor vehicle collision, cops said. He exited his car, looked over the damage and was crossing the eastbound lanes when a minivan driver rammed into him, cops said. It was not immediately clear why he tried to cross the highway. EMS rushed him to Jacobi Hospital where he remained in critical condition Friday. The minivan driver remained at the scene. No charges were immediately filed. In an unrelated incident two days earlier, Robert Thompson, 56, died after he was struck by a car while crossing the Cross Bronx Expressway near Gleason Ave. in Unionport. Thompson was crossing the highway when a 2011 Acura MDX driver slammed into him in the right lane, cops said. He was thrown into the far-left lane, hit his head on the pavement and died at Jacobi Medical Center, cops said.