Transit CLS issue - doors lock and immediately unlock again

[narfigator]

Hey!

Some time ago the locks on my Transit 90 T350 started acting up and eventually stopped working the way they are supposed to entirely. Now the doors lock and immediately unlock again - that is all doors (both front and the side door) except the rear door are actually locked and make the locking sound (see video) before unlocking again - the rear door seems dead, but can be locked manually from the inside. It doesn't make a difference if I lock via Fob, manually with the key or from the inside. I did clean the contact plate on the side door and checked for some obvious mechanical issue.

Here are some pictures and a video, maybe you spot something useful there: link

I did some research and it came down to either a broken wire, a faulty door contact switch or some issue with the CLS control unit. I was hoping one of you friendly lads could show me the best way to figure out what exactly is wrong, where to start looking and how to fix it. I'm not a mechanic but am generally able to fix things like that myself - the more detailed the explanation the better of course!

My primary goal is to be able to lock the front doors manually, since at the moment, there is no way for me to lock the car at all - the two doors in the back aren't that important. So, if someone can point me to a short term solution on how to simply disable the central locking system for the front doors, that'd be helpful.
It would be nice to fix the entire issue though!


Thanks in advance,
Nav

[loot]

All of the doors have a switch in them that is called the ajar switch and when the doors are locked the system checks that the switches are all reading as the door is closed, that is so the doors can't be locked while open or not shut correctly.
The front and rear switches are part of the actuator and the side door should have a pin switch.

A common failing is the wiring to the drivers side rear lock, it breaks up and stops the lock/ajar switch working

A drawback to the system is that if 1 fails then none of them will usually lock (although I've seen some mk7s lock and beep the horn to indicate a faulty lock scenario even tho all doors have locked successfully )

So, if your back door is dead then the loom that passed through the door needs checking and repairing or replacing, if it turns out that it is OK then the actuator may be suspect.

[narfigator]

The winner was the 'drivers side' aka right side rear lock wiring - gddmn brits - thanks for the hint!

Due to the questionable way they wired that cable and the motion every time you open/close the door, two out of the eight cables were cut - here's a pic.
Put em back together and everythings works as intended again, yay!

[ake]

The winner was the 'drivers side' aka right side rear lock wiring - gddmn brits - thanks for the hint!

Due to the questionable way they wired that cable and the motion every time you open/close the door, two out of the eight cables were cut - here's a pic.
Put em back together and everythings works as intended again, yay!

That's the one! Very common fault