My 2012 S60 t5 was showing "door ajar". After replacing the lock actuator with no joy, I started tracing wires. Just as so many have said, it was in the door boot! From the factory, zip tied wires that are too short.
Two wires cut apart and 3 wires frayed. The had to be removed to do the repair. The hardest part of the fix was the splicing of these wires. I had to add small pieces of wire to put it back together. I hope The uploaded pic
worked.