From the insurance dept website http://www.insurance.ca.gov/01-consumers/105-type/95-guides/... :
"If I am injured in an accident, does my health insurance pay anything?
Usually, your health insurance pays for your immediate medical care. Then your health insurance company will typically try to get back money from your auto insurance or the other person's auto insurance. When one insurance company tries to get money back from another insurance company, it is called subrogation."