Technical Ducato x250 Central locking issue, not the sensor issue

[RobbertN]

Hi all,
I've done some reading on this wonderfull forum but haven't found the solution yet.
Here's the situation:
Over the past year we sometimes had issues with the central locking of the van. At first it was just a matter of opening and closing the passenger door or the sliding door and the van would lock (by using the remote).
It happened more frequently and after a while the signal on the dashboard would come on while driving. It keeps flashing on and off (really annoying).
Now it will not lock at all anymore. When I press the middle button on the remote, the blinkers flash 10x and that's it. I'm also not able to lock all the doors by using the key in the drivers' door.

Here's what I did so far:
I checked and cleaned the contacts of the sliding door sensor checked
Checked the fuse F36, looked fine
Checked the flat black pin in the door sensor on the body side. When key is in contact and I press the black pin, the open door signal should go off, but that's not the case. (so I can rule out that this sensor is causing the issue??)
I adjusted the rear door catch inwards, so the rear doors are neat and tight shut.
All the locks are checked, cleaned and have some contact spray.

Still not able to lock it.
Funny thing is that when I start the engine, the open door signal on the display goes off, and I'm able to lock all doors with the button on the dashboard.
Then shut the engine off, exit and manually lock the drivers door. This way the van is locked, but it's not really a workable solution.
When the engine is running and I manually lock the doors with the button on the dashboard, all is locked but as soon as I drive for a while and hit a bump or take a corner, but open door signal is on again, all door are unlocked again.
I really hope someone can help me out with this.
Thanks for your time

 

[the green vanper]

Hello,

Have in mind that in the classic commercial van body there are 2 different locking buttons in the cab: on the central console and on the driver's armrest on the door. One of them locks all the doors, the other one only the back as far as I remember. Can't remember which one does what, as I have only the cab But I assume the armrest button locks the back of the van (because I don't have it).

For the BCM the side door(s) and back doors are 'back doors'. It can't differentiate which one is open.

The remote central locking works only if BCM knows that all the doors are closed. The flashing on the dashboard suggests it's the (typical) problem when the side door contacts have bad / insufficient contact. Or the back door loom is broken (most frequently the door with the handle, as it is used more frequently). It usually brakes in between the doors and the frame. Or just inside.

In first case cleaning the contacts and eventually repositionning them helps.

Just in case if I'm not clear enough, I'm writing about parts 1 and 2 on the diagram:

The other case is a little bit more complicated, as it requires some dismantling. After removing the trim (if you have one) and the rubber seal inspect visually the cables. You could also try pulling one end holding another end in the other hand. If the cable is broken you'll feel it

Checking the ground points can also be a good idea, but if you have only this one problem with locking the van, you can leave it for a better moment in the future. There is a ground points diagram on the forum with description.

EDIT: MES should help diagnosing, as it allows reading signals from the sensors and un-/locking the doors.

 

[RobbertN]

Hello,

Have in mind that in the classic commercial van body there are 2 different locking buttons in the cab: on the central console and on the driver's armrest on the door. One of them locks all the doors, the other one only the back as far as I remember. Can't remember which one does what, as I have only the cab But I assume the armrest button locks the back of the van (because I don't have it).

For the BCM the side door(s) and back doors are 'back doors'. It can't differentiate which one is open.

The remote central locking works only if BCM knows that all the doors are closed. The flashing on the dashboard suggests it's the (typical) problem when the side door contacts have bad / insufficient contact. Or the back door loom is broken (most frequently the door with the handle, as it is used more frequently). It usually brakes in between the doors and the frame. Or just inside.

In first case cleaning the contacts and eventually repositionning them helps.

Just in case if I'm not clear enough, I'm writing about parts 1 and 2 on the diagram:

View attachment 456282

The other case is a little bit more complicated, as it requires some dismantling. After removing the trim (if you have one) and the rubber seal inspect visually the cables. You could also try pulling one end holding another end in the other hand. If the cable is broken you'll feel it

Checking the ground points can also be a good idea, but if you have only this one problem with locking the van, you can leave it for a better moment in the future. There is a ground points diagram on the forum with description.

EDIT: MES should help diagnosing, as it allows reading signals from the sensors and un-/locking the doors.

 

[RobbertN]

Thanks for your reply. I'l have another look at the rear door mechanism, the loom and the ground points.
In our model, there door sensor is located on the rear end of the sliding door, and we don't have a lock button on the armrest.
I checked the MES website you shared, but unfortunately no service point near us, since we live in Spain. Do you think the issue could also be found with an OBD scanner? I see them quite cheap on Amazon. Or would that be a waste of money?

 

[RS3100]

One well known test for the contact plate on the van body to the rear of the side sliding door is to pack it out a couple of millimetres by pushing a piece of folded paper or card behind the edge. If the BCM then recognises that the door is closed, a more permanent fix can be made by gluing or bonding a slim piece of plastic of similar thickness to the same place.

I have also seen Fiat blaming this on the contact pin in the centre of the contact plate jumping more than one click at a time on its ratchet, pushing it out of contact with the door plate when the door is closed. On older vans, the pin can be reset from behind after removing the contact plate from the body (assuming you have access, many clad and lined motorhome conversions don't without some major dismantling). ISTR that later contact plates were modified to overcome this though?

 

[RobbertN]

One well known test for the contact plate on the van body to the rear of the side sliding door is to pack it out a couple of millimetres by pushing a piece of folded paper or card behind the edge. If the BCM then recognises that the door is closed, a more permanent fix can be made by gluing or bonding a slim piece of plastic of similar thickness to the same place.

I have also seen Fiat blaming this on the contact pin in the centre of the contact plate jumping more than one click at a time on its ratchet, pushing it out of contact with the door plate when the door is closed. On older vans, the pin can be reset from behind after removing the contact plate from the body (assuming you have access, many clad and lined motorhome conversions don't without some major dismantling). ISTR that later contact plates were modified to overcome this though?

Thank for your response.
I packed the sliding door sensor with some nano tape on the back of the plates, moving it a bit outwards. Unfortunately with no effect.
I also took apart the door-side sensor and loled to how I can set the pin more proud, but that seems to be not possible. I think the issue might not be the sliding door, since the warning on the dashboard doesn't turn off when I press the rectangular pin on the sliding door sensor on the body side..
Today I went to a garage and the guy didn't fancy this type of jobs , but gave me the contact details of an car electrician. Might be an option as a last resort.
Will keep you posted when we manage to figure it out

 

[the green vanper]

MultiEcuScan is a diagnostic software for FIATs and derivatives. It has a free version which shall allow such basic code readings and diagnostics. For details on the software and versions differences check their website:

Multiecuscan - Diagnostics software for Italian cars

The link in my previous post is an automatic link put by the fiatforum.com engine. It shows the forum users that are willing to help other users with diagnosing their vehicles. Fiatforum.com being an English forum, most of the users come from UK. Being in Spain I'd try checkig a Spanish forum, perhaps they have a similar functionnality.

In order to use MultiEcuScan you need an appropriate interface and a PC / laptop / smartphone / tablet. Depending on the system you might need a different license (especially for iOS). Details can also be found on the https://www.multiecuscan.net website.

Same for the details of the interface: it depends mostly on the vehicle model and the hardware you're planning to install the software on. Details can also be found on the https://www.multiecuscan.net website, too.

I've bought a lifetime licence and am a registered user. I have a KKL cable + one adapter (yellow?) and a bluetooth interface (STN1170) which allows me to use MultiEcuScan both on the road on my android smartphone with the Torque app for error codes clearing and basic monitoring and with the MultiEcuScan software installed on my windows laptop while stationnary for deeper analysis and more complex actions (like key programming).

 

[MSjoberg]

… allows me to use MultiEcuScan both on the road on my android smartphone with the Torque app for error codes clearing and basic monitoring ..,

Is this a typing error or is such a combination possible?

 

[the green vanper]

Is this a typing error or is such a combination possible?

Good point, I wanted to say I'm using the bluetooth interface both with MES on my Windows laptop and Torque app on the Android smartphone. I know there's a MES app on iOS, but it requires a wifi interface. No idea if there's a MES app available on android that will allow using a bluetooth interface.

 

[RobbertN]

Well, it's been a while but I finally solved the issue.
Apparently, it had to do with the household battery. Don't ask me why but since I replaced the old AGM batt for a fresh gel battery, the central locking worked as it should! Also, during driving we don't have the issue of constantly getting the error message of one of the doors being open. It might also have to do with the sensor not making proper contact.. I don't know but I do know we're really happy that this issue is now solved.
Thanks to everyone for thinking along and hopefully this post will help someone else in the future.