My two pennies, thrown in:-
Wound the window down, locked the van with 1 touch of the key fob, van deadlocks (you hear second clunk after the first one). Reach through the window pull the door handle, door does not open. The nob on the trailing edge of the door pops up as you pull the handle, but goes back down when you release the interior handle.
Second time round tried the b-post button to isolate the interior volumetric (often leave the dog in the van with a window down). Same finding as before, you can't open the van using the interior handle.
Third test, with the window open and one press of the key fob lock button, the lock/ unlock buttons by the mirror adjuster are equally isolated.
Now the real interesting one!!!!!!!
Fourth test. Open the window, press the key fob button once, get the double 'thunk' from the locking mechanism, now press the key fob lock button for a second time, you get a single 'thunk' from the lock. Now reach through to the interior door handle, pull it once and release and the door nob on the trailing edge of the door card pops up, pull the interior handle a 2nd time and the door opens!!!!
Conclusion. Pressing the key fob lock button once, turns on the deadlock, press it more than once cancels the deadlock.
This is the finding for my highline kombi Euro 5. Hope it sheds some light for others.
Just ran this past the wife, and she tells me she always presses the lock button on multiple presses to ensure!!!!!