Usually caused by a broken.
Transit side door lock jammed.
I had to take out the lock to repair and decided to show whats happening when rotary knob gets stuck.
In my case i could have probably unhooked the yellow.
How to get into a transit when the key will not work.
If the door panel cannot be opened enough to reach and view the door lock assembly search for possible partial disassembly.
Locate and remove set screws for the door panel.
Ford transit td280 04 plate jammed side door.
Updated 2019 04 16 video shows how to trigger stuck door latch on ford lincoln mercury mazda cars trucks vans and mini vans.