Ok, I followed the Haynes electrical diagrams today, found the wire, traced it from convenience system CCU to under the steering wheel. This was fine, no issues with the connection.

Next steps is under the steering wheel to the door latch (bit more work, have to take it off again, tape the window etc).


Before I do this, I also have an issue with the rear door:

Rear Lid contact switch (F124) - OPEN
Rear lid feedback - UNLOCKED

As such, the van will lock with the remote fob, but not flash the hazards (boot open symbol on dashboard)

I'm not sure what the "rear lid" is. The van has two barn doors. Rear left door contact works fine, and the light comes on when you open the door.

Does anyone know, if you leave the barn door (or tailgate) open, can you lock the van with the key, central locking, or does it unlock straight away?


I wonder if this rear lid is the real issue, and causing a false alert with the driver door lock.

 

Does anyone know if the rear lid contact switch is in here? Another £200 if so. Unless I can open it up and try some contact cleaner.

Note: not to be confused with the rear left door contact switch which is located in the bottom latch.

 

Interested to see what the fix is with this - my mate has very similar issues with his '07 plate Caravelle.

 

I'll get to the bottom of it @64 SPLIT .

If someone has barn doors, can they leave the locking door open, and try to lock the driver door with a key? And then try to lock with the fob?

I'd like to compare the results with mine. If it refuses to lock with a key and unlocks straight away, this back door might be my issue (I know it has an issue, but it might be "the" issue).

 

Can't help much with the barn doors but I do think it will not set the alarm properly if it thinks that the door is open.

I think the first code refers to the door locking barrel not the actuator. It looks like it's not recording that you have unlocked the door. You should be able to use VCDS live data to show if the key position is changing from locked to unlocked in VCDS. You could also try and see if turning and holding the key to roll the windows down works as a crude test for the locking barrel.

 

@T5 TDI thanks. I need to have the key in ignition to fire VCDS. I suppose I could remove the lock barrel and turn the lock manually with a screwdriver, not sure if it will like this with a key in the ignition anyway.

Another test.

If I lock with the keyfob. Then try to open the door with the key, the central locking works and unlocks, but opening the door the alarm goes off.

Unable to lock with the key, the central locking locks, but immediately pops back to open.

 

Below is the issue I need to fix first before the driver door.

Rear lid contact switch. Shows open when both barn doors are closed, see output below.

The door contact switches (ones in the latch) are working fine, and the light comes on when you open the barn door. (Theres no microswitch in the right barn door, and the drivers door was open at the time:

Not sure where this rear lid contact switch is located, might be within the actuator lock housing. I can't find any info online about disassembling the rear door one, loads for the front door actuators.

 

I think the rear lid switch is part of the actuator. Another quick test is to press the remote to LOCK twice. This should simply change the doors from being double locked to being single locked. When a rear actuator is faulty, the result of this double locking press is that the faulty actuator unlocks which is wrong.

 

Not my lock, managed to find a pic online. Got a feeling this is the switch causing rear door issue.

Unfortunately, I think if you open this up you get an explosion of springs/leavers and its a right pain to put it back

 

Rear barn door microswitches seem to be a common problem but never seen a decent fix other than replacing the locking unit you've posted above.

 

I agree with 64Split, I've had my tailgate actuator apart a couple of times, it similar to the barn actuator. It is really hard to set up the mechanism so the microswitches operate correctly.

 

Ok little bit of progress with this today. I cut a slot in the barn door actuator, save opening it all up, to find the switch above. It's fine, not a problem here.

I was incorrect with VCDS and the rear left door contact is my sliding door, not the barn door, so can ignore that.

Pulled wires from the rear latch, and tested with a multimeter. I found that the pre-latch (first click) wire was good (white 25). But main-latch wire white 23 was "always on". The door latches are a negative switch. So this white 23 wire is shorting somewhere.

Traced from the connecter behind the rear lights, white 23 connects to Brown/Blue wire. This goes to a red connector under the passenger dash side panel (only one wire in there). I disconnected this red connector and the light went out on the dash!!!!

A bit more troubleshooting and the Brown/Blue wire is shorting between the rear connector and the front red one. In the headlining somewhere. Impossible to find. So I've left it in its current state as always closed. I feel this is better than an always open rear door!

Hope this helps someone

 

Back to the original issue then. My driver door actuator.

I had an error of:

01031 - Central Locking Key Switch; Driver Side; Unlock
27-00 - Implausible Signal

A new actuator (old one was intermittent too so had to be replaced anyway) but the issue above still exists!

Anyone think I've got another faulty actuator?

Symptoms are:

• Cant lock central locking with the key, pops straight back open.
• Central locking works with key fob, but if I open the driver door with a key the alarm goes off.
• When central locking is unlocked, the van randomly clicks "unlock" all the time, as if I'm pressing the unlock button!!

 

Found it!!

My electric window motor!!

Wires to the driver door actuator traverse this, including for the "key switch".

I removed the YE/BU wire from the unit and directly connected. It all works perfectly.

I'm not quite sure why this passes through the window motor unit. Anyone know?

New units are hard to find and are expensive £200!

I might leave these directly connected and see how it goes.


For info, my driver door also cannot open the electric windows on the passenger side. Those wires also traverse the same motor. But it works fine for its own window!


I looked at the connections and there was some green/corrosion, cleaned all this up but still not working, must be a broken resistor or something.

 

What year is your van? As you probably know (as you have the Haynes manual) there are two different wiring diagrams for central locking on the pre-facelift, depending on year. On both of those, the Ye/Bu wire should go directly from driver's side door lock to Central Conv Unit T23/6 and not via anywhere else. I believe the function that this serves is to signal to Central Conv that the lock mechanism has successfully deadlocked. [Though I confess I don't have too much confidence in Haynes wiring diagrams!]

It may be worth paying a small amount for a subscription to erWin to get access to the wiring diagrams specific to your VIN.

One other thing - your photos are too tiny to see any real detail without needing a microscope!

 

It's a 2008. The key switch YE/BU goes via the electric motor. At a guess, I think this may be to trigger the "windows down" when you hold the key.

I've just put it back together, removed the YE/BU from the connector and crimped together. It seems fine now, done a VCDS scan and no issues oh and the passenger window switch on drivers side now works too (I guess cleaning the contacts fixed this!).

Think I'm going to leave as-is.

erWin, new to me but thanks this could be handy!

Oh and sorry I'm on mobile, next time I'm on desktop I'll re-size the photos

 

At a guess, I think this may be to trigger the "windows down" when you hold the key.

This is purely supposition, but I ~think~ the "Windows Down" function is triggered via the CAN connection to the CCU, and not via a separate wire.

 

After hunting here:

After market electric windows, one touch module

Can anybody help? I'm fitting a Travelinlite electric window kit with a one touch module to my 2010 T5. To enable the auto window closure function on locking I need to find the following, Automatic close trigger input. This closes the windows when the wire receives a negative signal. Connects...

www.vwt4forum.co.uk

Some info from people retrofitting electric windows. Seems like the Yellow/Blue could be for auto-close windows when locking.

 

I had to do a bit of sussing out years ago, made some notes - Model years 2004-2009
if this is any help to anybody..

Elect. window micro switches - drvrs door lock cyl - F241 yellow/ blue to CCCU
- pass door lock cyl - F242 green/ blue to CCCU

..and the Convenience Unit connection -

 

I've done some more digging, even though my issue is resolved, I have a slight worry I've skipped a necessary resistor/fuse by bypassing the electric window motor.

Bought access to erWin (thanks @triffic).

For reference, Haynes has a direct wire (if this is general, non-electric window setup, I guess I am good to skip and have the yellow/blue wire direct, as it enters the electric window motor for a feature, and not a wire/safety feature).

VW diagrams for my VAN, wire connects via electric window motor:

V56 below is driver door actuator, ge/bl is Yellow/Blue.

V147 below is electric window motor

Unfortunately, although I've found the wiring, I'm still none the wiser on WHY it enters the electric window motor.

 

Found a VW diagram that matches the Haynes above. Has the Yellow/Blue patched directly (via T10ae left side A pillar) to the CCCU.

I guess this is the non-electric window set-up:

If it's patched directly in some vans, I can't see a safety issue if I patch it directly in mine. But miss out on the auto-close function for electric windows.

 

If you go back to my previous post you can see the switch wire is yellow /blue, and the cccu connector wire to door is blue /yellow.
The up down trigger to cccu is one thru resistor, other not thru resistor.
My vehicle has OEM central locking & OEM elect windows.

Edit to say - if you check the diagrams you should not have a yellow blue or blue yellow connected to the J386, J387 door control units.

 

If you go back to my previous post you can see the switch wire is yellow /blue, and the cccu connector wire to door is blue /yellow.
The up down trigger to cccu is one thru resistor, other not thru resistor.
My vehicle has OEM central locking & OEM elect windows.

Thanks, yes matches up with my thoughts. Below is correct.

The Yellow/Blue wire from driver door actuator (key switch) connects to to CCCU (T23, pin 6), via the electric window regulator motor if you have electric windows, direct if not.

 

Yep, pardon me, there is a different diagram for 2008, & it does show the connection. It can get tricky sometimes. There must be something wrong in that control as you have found, ...they are often found to have moisture damage.

 

Yes I did spot some, took it apart and used contact cleaner but still had issues (fixed being able to lower passenger window from drivers side though!).

I did worry about directly connecting the Yellow/Blue and skipping the window motor as maybe it had resistors/fuses for the connection, but it seems as though on non-electric window variants, this wire is directly attached anyway to the CCCU!

A nice cheap fix