Hansen, 30, who is also a model with her own line of swimsuits, is being held on $1 million bail.
"I parked in my normal parking place, and I got out and all of a sudden I woke up in an ambulance," the victim, Elizabeth Conklin, told ABC News.
Police say Hansen waited until Conklin exited her car in the parking lot of the Diamond Head apartments in Waikiki before striking her. A bystander (identified by a source as a maintenance worker for the apartment building) witnessed the first attack and bashed in Hansen's rear window to prevent her from striking Conklin again, police say.
According to the police report, Hansen reversed the vehicle after the initial strike and attempted to hit Conklin – then lying on the floor of the parking garage – again.
Hansen left the garage after the incident but was tracked down by police. Investigators have not released a possible motive.
With reporting by CHAMP CLARK