Power latching - which wire to break into

[PhillH]

Hi all,

Looking for some help from anyone who has retro fitted power latching to a sliding door.

I have read that rather that running wires back to the BCM and door contact that I can break into a wire and connect T8x/6 and 8 in between. Can anyone tell me what wire this is? I know it is under the passenger seat but can not find more information.

All else fails I will run a wire back to the BCM

Thank you in advance.

Phill

 

[Pauly]

It depends on your van spec, is it a Highline with factory alarm or startline/Trendline without factory alarm ?

If you have factory alarm system then you need to interrupt the door switch cable which is connected in plug T10Q, this is a green 10 pin plug but may not have 10 wires in it (mine had seven) you are looking for the black/green wire in terminal 3 (not green/black) this wire runs from BCM to switch on B pillar

If you don’t have factory alarm then it’s a biege plug but I don’t have the wire number with me and will need to look it up if required

 

[PhillH]

It depends on your van spec, is it a Highline with factory alarm or startline/Trendline without factory alarm ?

If you have factory alarm system then you need to interrupt the door switch cable which is connected in plug T10Q, this is a green 10 pin plug but may not have 10 wires in it (mine had seven) you are looking for the black/green wire in terminal 3 (not green/black) this wire runs from BCM to switch on B pillar

If you don’t have factory alarm then it’s a biege plug but I don’t have the wire number with me and will need to look it up if required

Hi Pauly,

Thank you for replying so quickly.

It is a trendline with no factory alarm so it must be the beige plug as you say.

If you could give me the wire number that would be brilliant, thank you

 

[Pauly]

Im away for a few days wont be home until end of the week, feel free to message me then and remind me as i will no doubt forget.

 

[PhillH]

Thanks Pauly, I appreciate that.

I will try and have a look myself in the mean time too

 

[Pauly]

Sorry for the delay, im back home now and catching up on the back log

So

If your van is a highline/has a factory fitted alarm system then the wire you are looking for is in plug T10Q, this is a green 10 pin plug but may not have 10 wires in it (mine had seven) you are looking for the black/green wire in terminal 3 (not green/black) this wire runs from BCM to switch on B pillar

If your van is a startline or trendline your vehicle doesnt have a factory fitted alarm then the door signal will be going through a biege/brown 17 pin plug underseat and it will be a black/green cable in pin 4

If you dont have an alarm on yours the door open/shut signal comes from a door pin fitted on the C pillar at the rear edge of the sliding door, if memory serves correctly on those the signal is opposite to a highline lock generated signal (ie negative applied not negative removed) if this is the case then you may find the latching system operates in reverse ie open when closing and closes when opening

If this happens dont worry you just need to switch the power cables between the module and the motor, you can do this at the control module by reversing pins 1 and 3 in the 8 pin connector or you can do this at the motor by swapping the two fatter cables in pins 3 and 4 of the four pin motor plug (you will need to remove the sliding purple locking piece first)

 

[PhillH]

Hi Pauly, hope you enjoyed your holiday and thank you for getting back to me. You are right, I do have a door pin fitted on the C post. I will give this a try and see how I get on.

Thanks again.

 

[PhillH]

Hi Pauly, we are getting somewhere.

I have broke into pin 4 on the beige plug, connected pin 8 from the control module to the black/green wire coming from the switch and connected pin 6 from the control module to pin 4 on the beige plug. The motor activates when the door pin on the c post is push/release but the dash display is showing the opposite (door open when closed / door closed when open. I tried swapping wires 8 and 6 on the controller but I then loose the dash display. I also tried swapping pins 1 & 2 on the motor but this made no difference.

I also swapped the pins in the door pin connection but that did not make a difference.

From the door contact there is the black/green wire and a brown. Could it be I need to interrupt the brown wire? I can find this wire on the beige plug.

What would you suggest I try?

Thank you,
Phill

 

[PhillH]

So I think I may have a solution thanks to @Pauly @Dundee_Kev

Rather than interrupt pin 4 on the beige 17 pin plug if I tap into it with pin 8 from the 8 pin plug on the control module it operates as it should and the dash signal is correct. So pin 6 from the 8 pin connection is not fed back to the BCM.

This also means that the black / green wire can be tapped into in the rear quarter.

It is not fitted yet but I will report back and confirm once everything is working.

Thanks again.

 

[Dundee_Kev]

Hmm, interesting. Looks like I need to try this at some point. So we're looking at the door pin switch wire on the c pillar then?

I had tried so many combinations I lost the will to live at the time.

Good work

 

[PhillH]

So it works, I installed it tonight.
You can access the wire for the door pin switch on the C post in the rear quarter. I tee’d into the black/green wire here and connected it to pin 8 of the module plug. Pin 6 is not needed.

I can to pull the switch out as it did not detect the door straight away. The dash has the correct display when the door is open/closed.

This could also depend on the part number of the control module. I have the following:

7H0 959 243 H
SW: 0307
HW: 602

Hope this helps.

 

[PhillH]

So a update on this, I was not happy with how the power latching was working with the switch on the C post, with the switch extended all the way it would work fine but then it gradually pushed the switch in so the door had to be pushed hard for it to latch.

The way Pauly suggested would work using pin 4 on the beige plug and tapping into it with pin 8 from the latching control module but not connecting pin 6 from the latching module as that gave the wrong door signal.

As I had put the seat base / seat back in I decided to take a feed from the contact on the B post. I ran a wire from pin 4 of the door contact to pin 8 of the latching module. Then on the contact on the sliding door I had to bridge pins 3 and 4.

Now the door can be slid gently and the latching works perfectly, It can also be tested using a key to bridge pins 3 and 4 on the door contact on the B post.

 

[PhillH]

@PatoTT have a read through this

 

[PatoTT]

Hi PhillH, thaks for good info about this method. I was lucky and find original lock with microswitch and connector and buy it. For 35€ I didn't think twice. By the way, vw caddy has same lock in sliding door.

 

[PhillH]

No problem mate. Will you run a wire back to the BCM now?

 

[PatoTT]

No problem mate. Will you run a wire back to the BCM now?

I don't think that will be necessary. Switch in C pillar performs this function well. If I finish job, I write how it works.

 

[PatoTT]

Hi, I sucessfully finish power latch retrofit a few days ago, and all working great. My childs finaly close door at the first atempt, and for my surprise opening door is more simply too. Thanks for all info from this great forum and great peoples.