Driver side door panel is off so I can see what's happening. When door is already locked, turning key in door handle moves the latch inside door, unlocking door. Also microswitch seems to activate, causing similar action on passenger door.
However, when I turn key in opposite direction (to lock it again), I here microswitch activate and passenger door locks, but driver door does not. It looks like nothing is happening to flip the triangular piece on the latch in the opposite direction of when door was first unlocked. I haven't removed passenger door panel yet to compare action at that door to driver door.
Any clues?