I believe the autolocks don't engage when it thinks a door, hatch, or the trunk (on a sedan) is open, so that's probably not technically a 'fault'. The wire(s) running to the hatch may not appear obviously damaged or frayed to the eye. The copper conductor can break without damaging the insulation. ...

I'm thinking about the micro switches on the door latches or on the trunk. Try isolate the faulty part by pulling it's fuse if it has a separate fuse or try just unplugging the latches one by one (may require door panel removal)