Central locking switch

[Pauly]

Good work, happy to hear it's all sorted now

 

[DaveyB]

Ok I can finally bring an end to this, @Pauly sent me the wires terminated with the crimped terminal I needed, along with the correct plug to go into the back of the locking switch, and I had a day free so got stuck into it. I already had the door card off so was able to quickly attach the connections for switch illumination and ground, both available on the back of the mirror adjustment switch, and fed the remaining connector through the door wiring "tunnel" to below the steering wheel. The lower black trim has a couple of torx screws holding it then just unclips, and the trim on the lower half of the dash just pulls off. I also removed the shroud round the bottom of the steering column to give myself a bit more room.

Once upside down in the footwell you can see the two 73 pin connectors that go into the back of the BCM and they can be unplugged without removing the BCM itself by hinging up the white clips and pulling horizontally towards the front of the carView attachment 8550 (the flat side on the left goes into the BCM). To help distinguish them, one is white and one is black (I wanted the black one 73A), and pushing in a little clip either side allows you to slide the connector block out of the hinged surround. Once you do, you separate the connector block into two halves by holding the sides and sliding in opposite directionsView attachment 8551
Once you've done this you can see that each pin is numbered (they're very small but they're there) and once I'd found the pin I needed (25) I found that I couldn't put the crimped connector in as there was already a yellow wire in it. After further consulting with @Pauly he confirmed that was ok and to attach the wire to that yellow. That did prove difficult as it was in the middle of a thick bunch of tightly wrapped wires heading up the dash with hardly any slack, but after just a faint whiff of burning floor mat (oops) I had the connection soldered and heatshrunk. After reassembling the connector and plugging them both back into the BCM it was time to re-connect the battery and hold my breath and ... Success!

I really find putting the lower trim panel that fits round the light switch surround difficult and it took a lot of bending (and butchering the plastic round the surround itself, which is thankfully hidden when assembled) to get it back on, but with all reassembled it works perfectly and is indistinguishable from factory And yes I know the door card isn't back on properly, I can never get that right first time.
View attachment 8558

Boosted by the achievement, I then ran the cable for my rear dash cam and installed it, also running the rear cable for my upcoming 360 cam project, plus a spare 12v supply to the back while I had the trim off. All in all a good day, in fact I feel epic! Where's my high heels and hot pants

Huge thanks again to @Pauly for all the help, it's an unnerving experience pulling apart a 3 month old van and making new connections to the BCM and he gave me the confidence to give it a go If anyone ever needs to do this, or you've come across this on a Google search, get in touch and I can give you any more details you need.

Well played @andys, superb piece of work.

 

[goodfidelity]

Hello!

Thanks for the very useful info in this thread!

I would like to ad a couple of questions, since i have T5 model. I know this i T6 forum but all the info and pictures / detailed info is here so i feel i might continue on this thread for other users looking for same info.

- since this is just a one wire connection to the controller, how Does it know if the lock or unlock button is beeing used?

- will the result be same if unlock button is pressed two times?

- can a normal non latching push button be used for this hack?

- Does the pin on controller need +12v or god to activate the lock?

- is there anyone who knows the correct pin for the central lock controller on the 2008 T5, can i assume it is same as the T6?

- is it possible to just use a toggle button, to toggle lock / unlock, or is two buttons needed?

I am thinking to connect a GSM controller for webasto, unlock, alarm, lights.

That is why i am looking for this info.

I would be very happy if somone can fill the details.

Thanks for super good user input here!

//GF

 

[andys]

Hello!

Thanks for the very useful info in this thread!

I would like to ad a couple of questions, since i have T5 model. I know this i T6 forum but all the info and pictures / detailed info is here so i feel i might continue on this thread for other users looking for same info.

- since this is just a one wire connection to the controller, how Does it know if the lock or unlock button is beeing used?

- will the result be same if unlock button is pressed two times?

- can a normal non latching push button be used for this hack?

- Does the pin on controller need +12v or god to activate the lock?

- is there anyone who knows the correct pin for the central lock controller on the 2008 T5, can i assume it is same as the T6?

- is it possible to just use a toggle button, to toggle lock / unlock, or is two buttons needed?

I am thinking to connect a GSM controller for webasto, unlock, alarm, lights.

That is why i am looking for this info.

I would be very happy if somone can fill the details.

Thanks for super good user input here!

//GF

Hi, it’s been a few years since I did this but I’ll try and dredge my memory and help.
Note, all of the below may be wrong and subject to correction by someone more knowledgeable.

The connection to the BCM will provide 12v on side of the switch to lock it, and ground to unlock it (this may be the other way round, my memory is crap) so only needs the one wire.

It does need 12v, I didn’t invoke god to actuate it .

Pressing it twice while already unlocked would do nothing as it’s not changing state.

You can use other switches (and indeed many of us on here have done to have an extra locking switch to use while camping), but it needs to be a double pole switch so that you can provide +12v and ground to the control wire).

Can’t help you with the pin out of the T5 BCM, although I had a T5 I wasn’t a tinkerer then, but I’m sure the information is around. In fact I’ve still got my Haynes so I’ll see if it’s in there when I get home from work if you haven’t found it.

Control/monitor by GSM is certainly feasible, I’ve experimented using a Quark-elec box with some success. Good luck.

 

[travelvolts]

The lock is controlled by a negative pulse and unlock by a negative pulse via a 900 ohm resistor. On the T5 you can find the required connection behind the dash end plate on the drivers side. It is a thin yellow/blue wire in one of the multi plugs there.

 

[mmi]

Locking doors from the back of the van. ~ Stop me before I do something silly :P

Hi All Soooo. I have a long weekend and plan to do some bits and bobs on the van to make it more of a camper. One of them is to have a go at adding a secondary central locking lock/unlock buttons for the back of the van. Plan is to tap in to the switch on the driver door and run a switch in...

www.t6forum.com

 

[andys]

Told you my memory was b@llocks The 12v was from the lighting circuit

 

[goodfidelity]

Hello guys!

I see that there was some answers here and i did make a visit to the local stealer today to get some info. (after all i bought the cable from them, and that set me back about €16, they might as well cough up the pinouts and colors for the cables, very helpful they are!)

- In the T5 door there are three cables, these are GRENN/BLUE, BROWN/BLACK, YELLOW.
- The connector in the diagram has code name E150, and shows a resistor, 900 ohm as mentioned. So i guess 12v is one pulse, and 900 ohm 12v is another pulse.
- The cable out from this connector leads to the J393 comfort controller unit under passenger seat, but also has a connection in between under the steering wheel. On my 2008 car this is a black 8-pin conector. And this cable has pin number 8, cable is YELLOW. Cable number in diagram is 74.
- Connector on the comfort controller J393 is the big connector T23/6, that is pin number 6 on the 23pin connector. That is the larger of the two connectors.

Best way that i found out to locate the cable for this hack, is to just open the side of the dashboard (this plastic piece that comes off on the side) and locate the 8-pin black socket there, and make sure that there is a yellow cable coming out on the back side. This yellow cable can be pulsed to control the lock.

As of now i am not sure if 900 ohm pulse is lock or open, and vice versa on the 12v, i will try to come back with this info as of later.

I think that most transporter cars are missing the cable that is mentioned in this thread, that goes from the switch through the door and to the connector.

And its possible that this cable has different color from the door and out to the connector on some cars, if it is installed.

My intention is to install controller unit for this, and have some kind of appcontrol / siri control on the doorlock.

Thanks for all the help so far.

//GF

 

[goodfidelity]

Another update for those who attempt same modification.
(my intention has been to use app / GSM relay to allow for opening / locking the car, in addition to installing lock/unlock button inside the car)

I now managed to pull a female pin from the ISO harness from car stereo, seems those are same as in the 8 pin socket under steering wheel. This way i didnt have to splice into the harness, i just added another pin to the plug. From the plug to the controller there is already a cable running. However from the plug to the door / button there is no buttons.

As mentioned earlier grounding the yellow cable is verified to pull the doorlock, and adding the 900 ohm resistor will pull it other direction.

Sliding the purple plastic part bit sideways opens up the hole enough to let the pin enter. There was some wiggeling to get in place, not perfect fit, but works fine.

After trying to lock/unlock the door there was some variation in the effect and it took me a while to figure this out:
IF DOOR IS LOCKED WITH KEY-FOB IT WILL NOT OPEN FROM USING THE BUTTON TO ACTIVATE CENTRAL LOCKING.

I dont know if there is another way into the BCM / system how to activate / deactivate the alarm from inside the car. If not there will be possibility to order a cheap chineese keyfob and hook it up for further APP control.

 

[Wilemvh]

I have the same question Andys had. I have a T6 without the locking switch. I went to my dealer and bought the new switch and frame. I even have the blue connector for the switch with number 1K0972704G. After de mounting the door interior I found there is no cable for this switch in my T6, so I have to follow the same route Andys did. What are the schematics I need? @Pauly, is there a possibility to get a ready made cable for me as well? Thanks in advance from a T6 driver in The Netherlands.

 

[goodfidelity]

From the colorcoding in my post you can see what it is like in the T5, maybe different colors in the T6.

By no means you need any special harness, but that might make it look more nice.

Its just thin cables going, and you just need to understand the way it is controlled in order to operate it.

//GF

 

[Wilemvh]

Thanks for your answer, but I think I need the T6 schematics for the right colours and connections.

 

[Pauly]

I have the same question Andys had. I have a T6 without the locking switch. I went to my dealer and bought the new switch and frame. I even have the blue connector for the switch with number 1K0972704G. After de mounting the door interior I found there is no cable for this switch in my T6, so I have to follow the same route Andys did. What are the schematics I need? @Pauly, is there a possibility to get a ready made cable for me as well? Thanks in advance from a T6 driver in The Netherlands.

Pin 1 = negative (connect to any earth inside door)
Pin 2 = button illumination positive (connect to grey/blue cable on adjacent illuminated switch)
Pin 3 = empty
Pin 4 = lock/unlock signal (connects to pin 25 in black bcm plug (which will already be occupied))

The crimps you need to go into your plug are part number N90764701 but VW UK doesnt sell them anymore but if you google that number or the equivalent repair wire number which is 000979009 then you should be able to find something that will fit

10x Mqs Quadlock Socket Contact Pin -0, 5mm ² Fakra Most 000979009E Ungedichtet 744370601084 | eBay

About me Why we? Quality since 2001 Everything in stock shipping Payment Methods Bank Transfer.

www.ebay.co.uk

 

[goodfidelity]

The colours on my car was not the same as mentioned in this thread, so what i did was i looked for the one pin on the connector hub that had cable on one side, and was empty on the other side.

Then i did a simple measurment of that pin to see if it was live, and i did a grounding with the resistor between, then i got the motion / action from the centrallocking and i knew i found the right cable.

So you can work yourself around it if you like to give it a try.



//GF

 

[Wilemvh]

Thanks for your replies. I’ll gave it a try.

 

[goodfidelity]

Did you find it?

in my left-hand-drive it was under steeringwheel, left side in cabin, and close to the door. just by the OBDII port if i remember right.

 

[Wilemvh]

Nope, still waiting for the cable connectors to arrive. I am waiting for a week now and hope they do arrive before the weekend.
I will give an update around the weekend

 

[Wilemvh]

There was some extra delay because of the weather. I mounted the switch and the connector. And I got a wire from the door to the dashboard. I think it’s okay, because the light in the switch works as supposed. Now I have to find time to get to the BCM plug.

 

[Wilemvh]

Hello guys, getting to the BCM plug was easy. Getting the plug out was easy too, but I have no slack on the cable, so I don’t know how to reach pin 25. What’s the trick here?

 

[Wilemvh]

@Pauly I can’t connect to the black BCM plug. It doesn’t give me enough slack to get to the cable. You said plug 25 will already be occupied. Could you tell me the colour of this cable and where it is running to? Maybe I can find a better spot to connect. Thanks in advance for your help.