Locking was working fine on fob and just using key. Then all of a sudden, the central locking stopped working, when you press the fob, the indicators flash and the alarm arms, but locks don't budge. If you use the key in drivers door, you can hear the actuator make a bit of noise, but only when you unlock, not when locking! None of the other locks move either way! I've checked the fuse, just wondering what's the next thing in line to do? Thanks