Misterious disconnected wire in rear boot lid

[Jay-Jay]

Hi everybody and Merry Christmas!
Last day I was installing the rear flip camera and when I removed the rear boot lid, I suddenly found myself in front of a disconnected wire, which looks like a ground connector.





I honestly can't understand what it should be connected to, but all I can say is that everything seems to work fine and there are no errors recorded in the car's control units.
Could somebody help me figure this out?
Should I be worried?

[ciclo]

The wiring harness from which it comes is the one dedicated to connectors T5i, T5j (coupling stations). It is not clearly visible in the images but it looks like a 1.0 - 1.5 mm2 white wire (yellowish due to time?).

According to VW diagrams, there is no ground point built on the trunk lid for that eye terminal, check with the multimeter that it is a ground wire, if so you should not worry.

I guess someone was smoking something when building the wiring for your 6R, and upon realizing that he added an extra wire and knowing that it was a ground wire, he had the brilliant idea of adding an eye terminal in case you needed it for some retrofitting (plants help imagine possible futures and other divinities).

Merry Christmas!

[Jay-Jay]

Thank you, ciclo!
I think the culprit might be a guy who made a repair job on my car years ago...
My suspect is that the wiring harness has been installed upside-down and that yellow wire should be connected to the ground point behind the rear left boot panel.
Surprisingly, everything seems to work normally.
How can I check if that wire should be a ground wire considering it's actually disconnected?
And, once we'll be sure it is a ground wire, do you think I could connect it to another ground point in the trunk lid without having to reverse the position of the entire wiring harness (which would be a pain in the ass of a job...)?

[ciclo]

As I imagine you already know, with a multimeter you can check if it is a ground wire by 'continuity' between the eye terminal of the wire and the ground point that is on the C-pillar on the left side (preferably > 1 ), or the ground point that is in the compartment of the spare wheel, or any place on the body that you know is a good earth...
"biiiiip" > example in 1:10.
Maybe I didn't understand your question correctly...

If it is a ground wire and everything works on the trunk lid you can insulate the wire with cloth tape (for aesthetic or noise reasons) or leave it as is (a ground point in that place is fine in case you need it for any retrofits).


By the way, I recommend that 683 multimeter that is sold on Aliexpress for between 22-25 euros, it is very easy and 'pleasant' to use, for beginners/novices or not, it is very precise, it has a rechargeable lithium battery that lasts infinitely, and it also has a great carrying bag/box.
It is NOT perfect for very demanding people, but it far exceeds any expectation for that cost.

[Jay-Jay]

What I suspect is that yellow wire is not connected to any ground point at all, so I can't check the continuity with a multimeter as you suggested.
If that wire should be a ground wire and it is disconnected from any ground point, should I expect any malfunction?
What can I check to understand if that wire needs to be connected to a ground point?

[ciclo]

Mystery solved:


I would say that genius is 0.99% talent, 0.01% fortune and 99% hard work.

Note/Hint/Clue:
Not all 6Rs have that wire.

From my 6R, old image.


From the 'old/deep internet'.


Related diagram. Connection point not defined.



Parts. Very difficult to find and even imagine.
N10247302 https://www.ecstuning.com/b-genuine-vol ... n10247302/
WHT000025 https://www.ecstuning.com/b-genuine-vol ... wht000025/


Draw your own conclusions.

https://www.youtube.com/watch?v=uG476e4P6q0&t=161s

[Jay-Jay]

Well, that clears out the mistery!
It is definetely a ground wire.
Thank you, Ciclo!
At this point, I guess, my second radio antenna (specifically, the FM frequency modulation module) was not working as it should, despite not showing any error in the control units, but causing a lower radio signal.
I will surely buy the necessary parts and correctly connect that ground wire to the rear lid.

[Jay-Jay]

Well, to give a definitive ending to this topic, these are the photos of the final result.
Thanks again to Ciclo!

[ciclo]