The collision was reported just before 6 a.m. near the Havenhurst Avenue exit.
AIR7 was over the scene and captured the semi's trailer toppled over, causing an extensive backup for morning commuters. The trailer reportedly separated from the tractor and came to rest leaning against the center divider leaving the truck in center lanes.
The sedan reportedly sustained major left rear damage.
A SigAlert was issued around 5:30 a.m. to help clear the wreckage and clean up a diesel spill, the CHP said. Lanes 1 and 2 were reopened just after 8 a.m. but lanes 3, 4 and 5 and the Hayvenhurst Avenue off-ramp remained closed.
Injuries were not detailed but the incident was labeled an injury collision.
City News Service, Inc. contributed to this report.