2001 Honda CRV, when lock button is pressed rear PS door lock sounds like a machine gun (ra-ta-ta-tat) and door remains unlocked. Door cannot be manually locked either, what could be causing this? Is it likely to be the actuator gone bad, or just a mechanical jam up?
If you cannot manually lock the door, the power locks will not work because all it does is move the mechanical linkage. This sounds like the linkage or latch (the lock mechanism is in the latch) is binding on something. Take the door panel off and inspect the linkage and latch. You may have to take the latch out of the door to inspect it close enough.