The side door stays locked.
Transit van side door not locking.
Try opening the rear door driver side and operate the inside handle.
A great handyman site that specifies the above probable causes and more is the following link.
A short video showing a 2015 ford transit with a strange central locking fault.
Sometimes when you press the unlock button on the keyfob to unlock the rear of the van only the back doors unlock.
All doors are closed though.
How to get into a transit when the key will not work.
Aside from the fuses your drive side power door lock may be failing to work because of a bad door lock relay system or alternatively the locking switch button itself is not malfunctioning and in need of replacement.
If not if its the same then there is usually a sticking sometimes faulty lock mechanism on the van.
The only way is to lock it from the inside using the knob on the door.
I have a problem with my lwb ford transit 350 i can open the drivers door with key i can t open the passager door i can only open and lock the sliding manually i can t access the back doors from inside or open it.
When you then try to lock the van by pressing the lock button it relocks the rear doors and beeps the horn to say a door not closed.
Im depressed transit van gonna cost me a marriage if i m not careful.
The rear doors have a button of their own the side door wont lock or unlock using any of the buttons.
What happens is when it receives the lock signal because one of the locks wont fully lock as above it then kicks the locks open again as the system thinks there is a door not fully closed etc.
I have two fob but none worked if i try to open the back doors or reset the central locking by turning the the key on off 8 times in 10.
This happened on a 10 plate transit last year more than once.
Then lock it all up as normal.
But this prevents it from been opened from outside.
The cause of the fault is becoming a coming concern on the transit and the tr.