Ryan Cameron of Covey's consulting firm, Franklin Covey, said the author died 2:15 a.m. Monday at a hospital in Idaho Falls, Idaho, amid complications from the accident. He was 79.
Covey also wrote three other books that have all sold more than a million copies. He is the co-founder of Utah-based professional services company Franklin Covey.
The accident happened April 19 on a steep road in the foothills of Provo, Utah, about 45 miles south of Salt Lake City. Covey was unconscious and taken to a hospital, where doctors found some signs of bleeding.