BCM Connector pins and numbering system.

Littleblackflash

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Hi All
Finally I'm trying to run a wire from my tailgate conversion to the BMC. I've run the wire, removed the BCM and opened the black connector.

What I can't see is where pin 23 is in the connector.

Does anyone have a diagram showing where the pins are?

Thanks in advance
 

andys

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The numbers are actually written on the BCM terminals, albeit very small.
 

Littleblackflash

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There are, but I can only read pins 1-16 on one side and pins 57-73 on the other side. I can't see any numbers on the middle rows of pins. Unfortunately the plug doesn't have nice rows of pins so I could count them. The centre bit where I can't see has 3 rows of small pins with a double row at one end making it impossible to count them.
 

andys

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There are, but I can only read pins 1-16 on one side and pins 57-73 on the other side. I can't see any numbers on the middle rows of pins. Unfortunately the plug doesn't have nice rows of pins so I could count them. The centre bit where I can't see has 3 rows of small pins with a double row at one end making it impossible to count them.
Oh sorry, I must have been lucky with the ones I needed, think it was in the first row of the white connector and just remembered seeing loads of numbers
 

andys

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Are you sure they're not there, this post from the past me says I found pin 25 in the black connector and it was numbered, which must be close to the one you're looking for. Central locking switch Have you tried sliding the two halves to separate them?
 

Pauly

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Have you split the plug, it slides apart into half leaving two rows of connectors on each half
You can’t see the numbers on the inner terminals until you have separated the plug
 

Littleblackflash

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Perfect.
I didn't know the plug slits in half. Hopefully that would solve my problem. I've put it back together now but I'll try again soon.


Pauly
Do you have any pins to go Black Pin 10?
 

Littleblackflash

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I managed to get a few hours working on my van this morning. Pauly has sent me some pins so I can connect the tailgate lock to the BCM but I still can't get it working.

I've run 2 wires from the BCM to the lock, one goes direct to the lock motor and one goes to the switches. Earthing the switch wire should trigger the BCM to unlock the tailgate. But it isn't :(

I've connected VCDS and in Module 9, I've enabled what I can see for the tailgate. When testing an output, there is an option to test for Rear Lid Unlocking but it gives a message "This output is not supported by the control module". I hope this doesn't mean I need a higher spec BCM.

Any ideas?
 

Ads_Essex

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I managed to get a few hours working on my van this morning. Pauly has sent me some pins so I can connect the tailgate lock to the BCM but I still can't get it working.

I've run 2 wires from the BCM to the lock, one goes direct to the lock motor and one goes to the switches. Earthing the switch wire should trigger the BCM to unlock the tailgate. But it isn't :(

I've connected VCDS and in Module 9, I've enabled what I can see for the tailgate. When testing an output, there is an option to test for Rear Lid Unlocking but it gives a message "This output is not supported by the control module". I hope this doesn't mean I need a higher spec BCM.

Any ideas?
I didn’t, so id like to think you won’t.

But what was done to get it working I’ve no idea, I’m afraid.
 

Littleblackflash

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I did the same exercise for the heated rear window and that works. You can test the outputs and switch on the heated screen but I can't find anywhere to test the rear lid release. I also can't find anywhere to check the input into the BMC from the lid switch. Is there one?

When I find time I'll check the wiring connection by applying 12v to the pin at the BCM and see if the lid opens.
 

mmi

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You can test the outputs and switch on the heated screen but I can't find anywhere to test the rear lid release.
I have the test - see below, and indeed it unlocks the rear lid. All the output tests by @Dellmassive --> Dodgy Demister

Could it still be a coding issue? There are a few references of tailgate in the codings
1.--> Bcu Central Electrics Module 09 Byte Screen Shots
Other reference codings
2.--> Dodgy Demister
3.--> Dodgy Demister
4. Mine (tailgate with power latching):
-------------------------------------------------------------------------------
Address 09: Cent. Elect. (J519) Labels:. 7E0-937-BCM-V1.clb
Part No SW: 7E0 937 090 C HW: 7E0 937 090 C
Component: BCM PQ25 Max4 H82 0752
Revision: B9082001 Serial number: 4000 0491_____
Coding: A0A8393A0A61341393284F402DEB87F4C0947389604579C03304003F0860
-------------------------------------------------------------------------------
09-Rear Lid-Output test.jpg


I also can't find anywhere to check the input into the BMC from the lid switch. Is there one?
Tailgate status is at Measuring Blocks Group 006:
Field 2, field 3 = "Open", "Open" = when rear lid fully open
Field 2, field 3 = "Closed", "Open" = when rear lid ajar (at first latch).
In the picture below the lid was obviously closed.​

Door opening switch status is at Group 008, field 4. Just indicates that the switch is pressed, not related to actual latch operation as it depends on door status.
09-Rear lid-Meas.Blocks_a.jpg
 
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Littleblackflash

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Thanks MMI (Sorry I don't know you real name). Your post has helped loads but I'm still not there yet.

Testing the output in Address 09 didn't work. I kept getting an error message.

upload_2019-7-2_21-24-52.png

So I tried changing the start of the coding from
A0A4313A0A6134B193284FF47CEA9EF40FA070C960CC69603204003F0800
to
A0A8393A0A6134B193284FF47CEA9EF40FA070C960CC69603204003F0800

Note yours is
A0A8393A0A61341393284F402DEB87F4C0947389604579C03304003F0860

Some success, the module is now recognised, but the lid still doesn't open.

upload_2019-7-2_21-29-32.png



Testing the button was good, except the button isn't wired in yet. I've just earthed the wire from the BCM to test it.

upload_2019-7-2_21-33-10.png
and when earthed, it changes to "Activated" so I think that all good.
upload_2019-7-2_21-34-22.png

The red square changes to "Open" when the lid is manually opened. I can't get any response from the second field, even with the boot half latched.

It could still be a wiring problem. Any other thought?

And thanks once again for your help.
 

Littleblackflash

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I got the multimeter out tonight.

On the trigger wire to the lid handle, I get 5.7v which is the BCM monitoring signal cycling. Pressing the door release handle triggers a response in block 8 field 4 as my previous post.

I also get 5.7v on the wire to the lid release motor. So I'm guessing my problem is still a coding issue. If I apply 12v direct to the motor, it does release the lid so I know the lock motor works.

Any thought?
 

mmi

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Just looked into your coding - it looks like "byte 2 - bit 3" made the BCM aware of motor and enabled the output test.
A0 A4 31
A0 A4 39
Byte 02 Bit 3 Central Locking/Rear Lid: Spring motor (unidirectional) installed
----

The byte 7 has a bit for another type? of motor - and it is coded differently than mine. See --> VCDS codes list

Probably wouldn't hurt trying to change the coding from
A0 A8 39 3A 0A 61 34 B1.... (yours now) to
A0 A8 39 3A 0A 61 34 91 or

A0 A8 39 3A 0A 61 34 11 (as mine)

which would be changing B=1011 to 9=1001 thus changing the Bit 5 to be same as mine and as @andys in Dodgy Demister . Unfortunately the bit 7 isn't documented.

I think @Dellmassive has barn doors, and his coding for this byte is "31" = 0011 0001- so hopefully the bit 5 is the key...

Byte 07 Bit 5 Central Locking/Rear Lid: One-Motor-Lock installed
 
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Littleblackflash

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Thanks you !!! Success..

I quickly tried changing the coding from
A0 A8 39 3A 0A 61 34 B1.... to
A0 A8 39 3A 0A 61 34 91

I tested the output using the VCDS and the lock opened. Checked it with the door handle and that works too.


So my tailgater conversion is going well.
Lock - working
Screen wash pump - working
heated screen - working
rear wash wipe - not stated. New stalk fitted so far and that's it. I haven't checked with VCDS if the input to the BCM is registering yet.
Internal release button. - should now work but the illumination isn't connected yet.
 

Dellmassive

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I think @Dellmassive has barn doors, and his coding for this byte is "31" = 0011 0001- so hopefully the bit 5 is the key...

Byte 07 Bit 5 Central Locking/Rear Lid: One-Motor-Lock installed

Yes correct, i have Barn doors version.

Glad its working, great detailed job there @mmi well done.
 

mmi

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upload_2019-7-2_21-34-22-png.46505


The red square changes to "Open" when the lid is manually opened. I can't get any response from the second field, even with the boot half latched.
Glad to hear it's working :thumbsup:.
A bit curious if now Group 006 both fields 2 and 3 change to "Open" when the lid is fully released from the latch.
 

djmeeg

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Hey, everyone. @Littleblackflash, I am in the process of fitting a tailgate to my swb T6. And cming accross the same issue. I am just not sure about the wiring harness. Does anyone know which pins I need to use for the latch and the motor acuator ? Also where I can run the power to the reg plate lights ? I can have the van coded afterwards, but the barn door tailgate wiring harness isnt much use. So I was going to make another harness for the tailgate and plug it in to the connector in the NS rear quarter. But no idea which pins do what as they are all white. It very difficult. Any help or advice people would be a great help
 
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