The girl told family members in the hospital on video she was cold and hurt.
The California Highway Patrol says the crash happened about 1 a.m. Sunday on a semi-rural stretch of the Sierra Highway in Acton.
The girl reportedly walked through rugged terrain and eventually wandered into a commuter rail station and told a security guard what had happened.
A coroner’s spokesman identified her father as 35-year-old Alejandro Renteria, of the North Hollywood section of Los Angeles.
The CHP is investigating whether alcohol played a role in the crash.