left rear door will not lock or unlock with interior switch or key fob likely cause ?
One of 2 things are wrong. Either the door lock switch is either disconnected or bad or the door lock actuator. Take it to a body shop (much less expensive than a dealer) and have them pop the door trim panel and check it out. Part new is available on amazon.com $16.46 (switch) and the actuator with motor is $64.00.
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