Can't get rear fog-light to work on my 6R Blue GT after upgrading the BCM

[ciclo]

Hi Aquavalver, none of that is necessary, forget that idea, there are no different codes or reference numbers for the BCMs of RHD or LHD models (for the UK or any other end of the universe).

We already told your BCM via the Gateway that your vehicle is a RHD.

From here on, there is no difference between both models, the electrical installations (BCM connections) are identical, just that 'things' are placed on the other side, as simple as that.

Yes, getting autoscans is sometimes difficult, search with google -'use your autoscan data'- (copy-paste), you will usually end up finding many scans where it is mandatory to post them, i.e. on the Ross-tech forum.
My Indian friends have 6R family vehicles that are also RHD (POLO, VENTO), in fact it is with them that we have the most experiences.
Here on the forum there are a couple of Indian Masters/Doctors.

You must get out of the closed circle in which you find yourself.
Change your diagnostician, or better yet, get the VCDS and I will provide you with everything you need to know.

[ciclo]

Aquavalver, you need to do the following to get your rear fog light working with the BCM 7E0:

1
- Run a 0.5mm2 new wire from the T17/9 light switch connector to the T73b/43 BCM white connector.
You need to remove and properly insulate the original T17/9 wire.
A wire length of 120 cm should be fine.

2
- Run a 1mm2 new wire from T73a/6 BCM black connector to the T6/6 right tail light connector.
You must remove and properly insulate the original T6/6 wire.
The wire length should be between 4 to 5 meters.


The problems with the rear fog light on your BlueGT will be over.
It may be necessary to recode the BCM 7E0, the results and the diagnosis will tell us what to do.


If this job is going to be done by someone other than you, copy this info and give it to whoever is going to do the job.

[NHN]

Thanks for the input, I'm the retrofitter working on this car few times before & this issue,, so I'll check over the coding & wiring changes mentioned, I'll compare both modules wiring in Erwin, Elsa & vcds coding.should be able to resolve it, I'll report back when sorted.

[ciclo]

Hi, don't hesitate to ask me if you get stuck at any point, we will fix it YES or YES, you can be totally sure.

For the PQ25, taking photos and a recent/fresh Autoscan always help to solve problems more quickly and easily.
I'm sure it's a small problem that will be resolved quickly.

[NHN]

Aquavalver, you need to do the following to get your rear fog light working with the BCM 7E0:

1
- Run a 0.5mm2 new wire from the T17/9 light switch connector to the T73b/43 BCM white connector.
You need to remove and properly insulate the original T17/9 wire.
A wire length of 120 cm should be fine.

2
- Run a 1mm2 new wire from T73a/6 BCM black connector to the T6/6 right tail light connector.
You must remove and properly insulate the original T6/6 wire.
The wire length should be between 4 to 5 meters.


The problems with the rear fog light on your BlueGT will be over.
It may be necessary to recode the BCM 7E0, the results and the diagnosis will tell us what to do.


If this job is going to be done by someone other than you, copy this info and give it to whoever is going to do the job.

Now had a chance to look at schematics, I see where youre going with this, the fog light was maybe controlled via the headlight switch to the fusebox which fed the rear fog direct whereas the other route was via the bcm which shows up in elsawin aswell, I'll check this tomorrow or thursday, seen this on a B7 A4 when I upgraded to bixenons for client, fogs were moved to the bcm from the headlight switch.

May have to add a .35 for the dash fog warning light unless its already there as its shared on the t73a/6 pin that supplies the fog light.

Good shout, touch wood that'll work.

[ciclo]

I seem to recall that the 7E0 BCMs can manage the rear fog light warning signal for the instrument cluster via CAN Bus (with the right coding).
However, it's good to know that if this isn't the case, you can add a "NEW" 0.35mm wire to the T32/13 connector on the instrument cluster for this warning light. The original wire will already be there from the original electrical installation, which must be insulated once replaced by the new wire.

I recommend that you first verify that the rear fog light works without the taillight being connected to the car's wiring... providing 12v at the appropriate pin. Some non-original taillights were manufactured without rear fog light.
Or if possible, and it's the most advisable, you should work with the original taillight first.

[NHN]

i'll use the existing fog light wire from the switch & extend to the bcm, no need to run a new one, this way I can test the theory temp & then properly solder, heatshrink etc.

Yeah I saw the wire in the cluster in elsa, so thats easy enough.

Thanks.

[ciclo]

Ok! That's good.

I just thought a complete rewiring of the rear fog light was going to be done due to the previous issues.
Hmm... I think this issue has been with us for at least a year or two, the never-ending story...
Let's hope that this time we solve them definitively/permanently.

[NHN]

Nah the wires fine, its just the coding & location of said wiring to be fitted lol, its a carbon copy of that b7 I worked on.

I'll be working on it tomorrow or friday so touch wood it'll be resolved.

Yeah I've only now had a chance to get my teeth head into it & check through elsa, I can see the differences even on the same year which backs up what you were saying theyre the same for 6C & 6R, just difference in modules eg highline as opposed to midline.

[NHN]

Do you happen to have a complete wuring diagram for the 6C at all please, as strangely my elsa downloads is missing the basic wiring pdf amongst the thousands Ive got lol, if not then no worries.

[ciclo]

The only wiring diagrams you should use are for the 6R or PQ25 platform (Transporter T6, Amarok 2016, etc.)
The POLO 6C is a completely different platform, so nothing to look at here.
6R... 2009-2014
6C... 2014-2018

The following link contains the erWin PDFs for the 6R and 6C, which include wiring diagrams for both.
https://drive.google.com/drive/folders/ ... sp=sharing
Please request the download, it will be granted as soon as possible.

[NHN]

Thanks.

Afaik the 6C is just a facelift, probably updated bus systems etc but I need to check the heated seat buttons as although I solved the issue, I just want to clarify somethings, the buttons appear to now be wired identically whereas the previous 6R were pinned differently between L & R, as I updated this guys buttons yesterday to the newer smaller ones that also has a slight vent edit, managed to figure out the pinouts but curiosity.

[ciclo]

Well, the 6C is PQ26 platform, an experimental spawn with PQ25 6R structure, we could say that they are similar in appearance with different electronics.
The PQ26 and PQ27 are the prelude to the MQB-0.

Fortunately, VW continued to evolve the PQ25 with the T6, Amarok, etc. and the 6R family in different places of the world.

For the installation of smaller switches (6C), with the wiring diagrams you have downloaded you can verify and compare everything you need to know for the pinouts of the dashboard switches.

[NHN]

Yeah just checked & I do actually have all these diagrams duhhhh, thanks.

Yeah they chnaged the heated seats button wiring so drivers & passengers matches except the button pins 1 & 2 are reversed on the heated seat module j774 for drivers button, I wondered why it was reversed leds lighting up as opposed to passenger side.

[NHN]

Well, the 6C is PQ26 platform, an experimental spawn with PQ25 6R structure, we could say that they are similar in appearance with different electronics.
The PQ26 and PQ27 are the prelude to the MQB-0.

Fortunately, VW continued to evolve the PQ25 with the T6, Amarok, etc. and the 6R family in different places of the world.

For the installation of smaller switches (6C), with the wiring diagrams you have downloaded you can verify and compare everything you need to know for the pinouts of the dashboard switches.

They were all fitted yesterday, just 1 minor edit by friday.

Do you work for vw aka vag in the manufacturing, design etc side or just knowledgable on the platforms.