Heated Seat Retrofit - Climatic unit & Kufatec loom

[SteveCole]

Hi all,

This is my 1st post to the forum, and I was hoping this would be a handy how to but instead I am after a helping hand. I have had my T6 Kombi for a few months now and I have decided to retro fit the genuine heated seats, in the summer Not seen a full how to so I thought I could contribute however so far its not been going well. I have fitted the genuine seat pads, control module and aircon control. The bit that I am struggling with is the Kufatec wiring instructions! They make very little sense and as access is so limited I am really struggling.

1st off it says I need to connect into the fuse box (SC25) and install an appropriate fuse, SC25 already has a 10A fuse and from what I can see this powers the heated washers and rear wiper?? However SC27 looks like it should be for the original heated seats (which is an empty slot) Should I be tapping into this or am I meant to be putting a 90 degree Add A Circuit fuse holder into 25?

The next issue is cable K1.86 to a relay? Apparently is goes to designation J29 and is an X-Contact (relief relay) It's called cable K1.86 as it goes to terminal 86 and pin 1 of the Relay. All sounds well and good but I have no idea which relay it is? I have two above my BCM module, (646) + (524) when I emailed Kufatec they said it should be a relay that is imprinted 449? I have double checked and I definitely have the right loom (according to them) however Kufatec didn't take any pictures during the instal so I am finding it very difficult.

Next it is saying about connecting cables A54 and A35 into plug A of the BCM module to pins 54 and 35. when I tried to fit it, it already has a pin in 54! what is going on here, it is so frustrating! I can add photo's if this might help someone? I just didn't want to confuse matters.

Thanks in advance
Steve

 

[Ads_Essex]

Welcome, Steve.

I don’t know the answer but will be interested to see how you get on.

I think you may be the first person on the forum to have got as far as you have - it’s something a few of us have looked in to, but not pursued.

Hopefully someone on here will have some more info.

Keep us posted if you find the answer elsewhere

 

[Pauly]

Do you have wiring diagrams for the seat circuits ?
Do you have the additional relay to control the seats ?
Do you have the instructions on pdf or paper, should be able to help you but would be good to see what you are seeing first

 

[SteveCole]

Well so far I have done bit more digging. Thanks to joining the VIP section I can now clarify which relay I need! Relay 644 and pin 1. This relay is in fact located next to the fuse box not above the BCM as the Kufatec instructions suggest.

I also managed to get a proper copy of the fuse layout, SC25 is the rear wiper fuse which I confirmed by removing and trying the wiper. This means that SC27 is the fuse location I need for the heated seats and I also need a 25a fuse.

I just need to confirm i can use the red and white cable of SC25 to tap into that to feed SC27. I will update as I go

 

[Pauly]

The feed rail should be common across all those fuses, does the supplied cable have a terminal crimped onto the end it ? If so then you can remove the fusebox take of the rear cover and click it into an empty slot, doesn’t really matter exactly which one as long as it’s on the same power rail

 

[SteveCole]

Sorry Pauly, just seen your reply. I don't have a wiring diagram for the seat circuits and couldn't find anything in the downloads.

I do have the additional control relay: 5K0 959 772 A

I have the Kufatec instructions on both a PDF and Paper

 

[Pauly]

Can I have the Kufatec pdf please, either post it here or send to admin@t6forum.com so I can have a look and I will get you the factory seat heater wiring diagrams (will need a bit of time as just been evicted from pc by the kids)

 

[SteveCole]

No problem Pauly, that would be great!

I will take a photo of the wiring and upload it soon, hopefully it will help shed more light. I will email you over the PDF.

The next question is what pin should I be using on the BCM?

They suggest Pin 54 and 36 in plug A however pin 54 already has a cable going into it. From memory it was Red and Brown going into pin 54?

Cheers
Steve

 

[Pauly]

Looks like fuse 27 is the one and the only BCM connection shown is 36 ?
I have PMd you a pdf of the seat wiring

 

[Deaky]

And this is why it pays to be a VIP member. Great work @Pauly

 

[Pauly]

For the benefit of others heres the instructions i received



Think i would follow the cable K1.86 in the provided loom and see where it goes, you can then compare the wire source to what the wiring diagrams i sent you show

Can you clarify, do you have the external relay (labelled J774 in the wiring diagram) its a black relay with a black or blue connector housing like the pics below

 

[SteveCole]

Ok, So I think the red hearing that was tripping me up was this red and white cable that was strapped to the white cable. I don't think it needs to be there, the white SC25 cable is pre made and will fit right into SC27. This Kufatec have it labelled up wrong.

The cable that isn't pre made goes into the X-Contact relay which is relay 644 located along side the fuse box.

Earth cable is self explanatory.

Which now just leaves the 2 pre made connectors for the BCM. Thanks to Pauly, we can confirm that A36 is the heated seat cable and as you can see in the photos in empty, however I don't understand what pin 54 is meant to be for as this slot is already occupied?

As I have said I am using a genuine VW parts which I will list below.

VW Aircon Unit With Seat Heater Buttons: 3C8 907 336 AC
VW Seat Pads Base: 7E0 963 555
VW Seat Pads Back: 7E0 963 557
VW Heated Seat Control Module: 5K0 959 772 A

I feel like I am so close now, if it all goes successfully I will be uploading a How To!

 

[Pauly]

 

[SteveCole]

Any idea what pin 54 is for Pauly?

I have just had another look at my Van, the Red and Brown cable in the BCM that comes out of pin 54... Is that possibly the same red and brown which goes back to the Relay (644)

If so, can I tap into the BCM cable 54? Is that done practice or should the BCM only have 1 wire going into each pin.

 

[Pauly]

Follow the cable labelled 54 in the kufatec loom and see where it goes, if its the other end of the K1.86 then theres a good chance it is

 

[Pauly]

Not sure if its any help but found the relay location picture

 

[SteveCole]

Cheers Pauly, It's more to confirm that pin 54 out of the BCM definitely goes to relay 644 and also that I am ok to splice into it as it is a pre-made connector, which again might not mean anything, but I don't want to cause any damage.

I have tested continuity between K1.86 and cable A54 and can confirm that they are linked.

It's pointing to the fact that this is just a link wire between 1.86 and 54 however I really want to confirm I am right in thinking that before cutting into the wiring loom.

I am tempted to put a multimeter across the relay and the BCM however it is raining cats and dogs outside and I don't want to disconnect the battery and have the van open in the rain. Likewise I don't want to do it live incase the cables are not linked and I spike the BCM.

If anyone has a diagram and can confirm then that would be amazing! As i can start putting a proper how to thread together.

If no one has access to this then providing it stops raining later I will run a meter across these two cables.

 

[SteveCole]

Result!!!

Rain has stopped, so I disconnected the battery, pulled the relay and guess what, pin 1 has continuity to pin 54 meaning all I need to do is splice into that cable and we are away!

Fingers crossed I will be tackling the rebuild tomorrow, I will take photo's along the way and get a how to posted if it all goes well! I have a feeling I might need to get it coded, but I know a local company with VagCom software so if I do I am hoping they will be kind enough to do it for me

Total investment so far has been around £500 with postage etc.

£300 in heated seat pads
£69 for the control Module
£50 for the Aircon Dials
£70 on the loom.

Hopefully this works tomorrow. I know you can get cheaper heated seat options but when all is said and done you can't beat factory.

 

[tom200uk]

Hi, did you get it all working in the end?

I have tried fitting today with the kufatec loom but the instructions don’t marry up well at all.

Did you have the right spaces in the ac control panel free? (12-13) Mine are already used.

I also have 54 already used like you but do have the 449 relay behind my bcm.

What age is yours? Mines a 2015 high line 180.

 

[tom200uk]

I have mine all working fine now.

Very simple. If pin 54is already taken it meant it didn’t need the K1.86 cable connecting at all as pin 54 was already connected from factory.

I have a spare loom with instructions if anyone is interested.