2014 Citroen Dispatch, rear door lock, help needed desperately please!

[Iainalleway]

Hi everyone, I have a 2014 Citroen dispatch, my rear doors lock with the central locking, however will not unlock! You can hear a click in the rear door when you press the button! I have had to unplug the door to stop it locking so I can still use the van, you can sit and click the button to lock and unlock a million times for like 20 minutes before it actually unlocks, sometimes it won't unlock at all! I have replaced the rear doors however the old doors had a similar issue, it would lock perfectly fine but would take a few attempts at unlocking for it to unlock the back doors, not as bad as the current door though! Any help would be appreciated please!

[mickthemaverick]

This type of problem is usually caused by the magnet not having sufficient power to pull the release because the catch is too tight due to being desperately in need of lubrication or more often misalignment of the catch and its housing caused by continual slamming of the doors or even a minor impact such as reversing into a post or something. Check that the catch can locate easily into the keep and that alignment is all good.

[Iainalleway]

Can you explain what you mean by the alignment of the catch? As the handle doesn't attempt to unlock the catch once the door is locked? I may be misunderstanding here so I apologise if I am, even if the door is open and I lock it (bypassing the sensor) it still won't unlock by the button?

[mickthemaverick]

Within the lock mechanism there is the normal catch operated manually by the handle and there is a locking device which blocks the catch from opening and hence 'locks' the door. It is that locking action that I am referring to. If it is too difficult to release then the magnet will not be able to move it when energised by your button. IIRC the lock operates two vertical rods which engage into sockets in the top and bottom of the frame. If one of those is bent or misaligned it will be hard to release. The same will be true of the locking mechanism inside the latch. Try a good dosing of lubricant and see if it makes any difference.

[Iainalleway]

Thankyou mate, anywhere in particular I should try lubricate on the mechanism?

[mickthemaverick]

I'd spray all the bits you can see with silicone maintenance spray working inside the van.

[Iainalleway]

Perfect thankyou for your help, I will update the thread later today once I have tried this, fingers crossed

[Iainalleway]

So sprayed everything within sight but no joy unfortunately, not sure what to do now!

[mickthemaverick]

Can you check that the lock unlocks with the key without excessive force? If that is not apparent then you may have an odd electrical fault which I cannot help with off the top of my head. Logic says the remote is sending the signal for locking so its transmitter is working. Assuming you have a different unlock button then it may be a dirty contact in the remote on the unlock button. If it is a toggle type lock/unlock button then you can move to the receiver and relays. This is all me thinking logically without referring to the actual system but it may give you a way to go.

[Iainalleway]

Hi mate, yeah it unlocks fine with a key, but its a long story but ive borrowed my friends spare key as its his old doors on the van but obviously he needs his spare key back. The van does the same if im unlocking it via centre console or the key, or by twisting the key in drivers door, all doors unlock except this one, however if I turn the key in the back door it unlocks all the doors on the van, im baffled... you can hear the back door clicking when you unlock the van it just doesn't actually unlock


Thankyou for your time

[mickthemaverick]

OK so if you hear clicking at the back door when pressing the remote or button unlock, it suggests the system is sending a signal to the lock but the magnet is not operating properly. That could be due to a high resistance fault in the unlock wire causing a voltage drop and not enough voltage at the lock to operate it fully once it engages the mechanical load of the latch. Can you check the voltage at the lock (unlock wire from the diagram) with a multimeter when pressing the unlock button. It should be a healthy 12V. If not then you need to trace the wiring back from the lock checking for chafing and sharp bends where some strands may have broken, clean connector plug pins throughout the loom and general good condition.

Unfortunately I don't have access to the parts diagrams or wiring diagrams for post 2013 vehicles, you will need a member with their own access to help you with those. However I am attaching those documents from a 2012 model which may be very similar and give you an idea of how it works. I'll also add a guide to interpreting the wiring diagram which will help. Beyond that I'm afraid I can't help anymore. Good luck

DISPATCH III - 0380 07 848101A - REAR HINGED DOOR LOCK.pdf

Parts

(195.2 KiB) Downloaded 71 times

dispatch locking wiring.pdf

Wiring

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Wiring Diagram Guide