Ford KA passenger door locking problem

[Essex200]

2004 1.3 Ford KA 80km

Our 2004 KA passenger door lock is behaving odd.
Using the drivers door I can lock and unlock both doors.
If I turn the key on the passenger side it immediately re-locks.
The same happens if it is unlocked. Turn the key in passenger side and it locks and immediately unlocks.
When sat inside the car, as if trying to lock myself in, I can push the door handle on drivers side and both lock.
If I push passenger side, it immediately unlocks again.
Now the odd thing.....
If I unplug the drivers side door loom (near the hinge) the passenger door lock behaves normal.
I can use the key to lock and unlock.
When sat inside the car I can push the passenger door handle to lock it and pull it to unlock.

Any advice is very welcome please?

Thank you
Ian

 

[Spark123]

Probably a broken wire in the rubber boot which plugs the door into the bulkhead.

 

[Essex200]

Found the problem it was a short circuit diode in the drivers door locking motor assembly. Replaced both with 1N5401......sorted