CUSTOMER CONCERN The left rear power door lock did not operate normally, even though the lock actuator worked when powered directly. CAUSE Testing confirmed that the shared body-control circuit still operated the other locks, isolating the failure to the dash fuse box. CORRECTION The dash fuse box was replaced, restoring normal door-lock operation.

Diagnosing a 2017 Toyota Prius door lock that does not operate from the power lock system. Learn how actuator testing, Main Body ECU commands, wiring and the dash fuse/junction box can help isolate the fault before replacing components.