Skoda Octavia Drivers door lock failure.

Car; 2018 Octavia Scout Low Mileage. No VCDS diagnosis.

Symptoms:  Central locking working but not locking the drivers door, or sometimes not unlocking the drivers door. This is with the key fob or the auto lock feature or the central console button. The car would lock using the manual lock function beneath the door handle cover.

This would suggest that the wiring is all in order. With the door card removed no amount of wire wiggling would change anything.

Solution: Replace the lock module. It is no longer possible to dismantle the lock module, at least not easily. The mechanical and electrical parts of the lock module are now riveted together instead of being screwed. (or possibly shear bolted).

To remove the lock, first remove the door card. It is possible to leave some of the electrical plugs attached and just turn the door card at right angles stood on something like a box. See you tube for removal methods.

To extract the lock you need to remove the lock barrel. This is done by removing the small black weather seal on the outer door edge to reveal two torx 20 screws. The black one needs to be fully removed the silver one need to be undone until you feel resistance. With the key in place, push in on the silver screw and the lock barrel will then easily come out.

The lock unit is removed by undoing the two spline bolts with a M6 xzn 12 point spline tool. detach the cables from the lock. Then fit the new one in the reverse order. 

I think the lock modules have possibly been modified as they have a number of part number updates.  Part No. 5TC837016D    defines as a latch.

This must be a common fault as the parts dept. had one on the shelf.