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(HELP) RETROFIT Auto Dimming Rear View Mirror MK3 Leon

Hussam

Active Member
Jan 6, 2019
15
0
England
Hi,

The first owner of the car did not purchase the Convenience Pack, and therefore, I am left with non of the following:
Auto-dimming rear view mirror - Auto headlights with automatic coming & leaving hone function - Rain sensing wipers

The car is SEAT LEON FR (150) 2017 Facelift, it comes with humidity sensor which I will be replacing it with a new Light Rain Humidity sensor as the harness already there. However, I am facing an issue, I have been trying to find any topic to discuss this retrofit of the auto dimming rear view mirror and no specific guidance is available.

I have purchased the following kit
https://www.aliexpress.com/item/OEM...ml?spm=2114.10010108.1000023.3.68f37e413mrQPv





Could anyone please help me identifying how to connect the Auto Dimming Rear View mirror cables/harness to the car. and if possible how to remove the humidity sensor?


All I got is this diagram however I do not understand it. The current cable I have is the G823 for the Humidity sensor. Please help.



Thank you.
 
Last edited:

astaller

Active Member
Dec 20, 2018
24
3
Germany
Wow, a big package...

For the mirror you need only the cable and the mirror.

How to connect the auto dimming mirror:

In a German forum is described how to attach the mirror.
I translate that for you into English:
  • Mirror plug T8q/pin 1 goes to the OBD diagnostic plug pin 1 (black/green, ignition plus 12V, or attach this cable to an other existing ignition plus cable)
  • Mirror plug T8q/pin 2 goes to the on-board control unit (J519) to plug T73c/pin 63 (brown, ground line 0V, or attach this cable to an existing ground cable)
  • Mirror plug T8q/pin 3 goes to the on-board control unit (J519) to plug T73a/pin 64 (black/blue, signal for reversing light)
  • Mirror plug T8q/pin 6 goes to the interior light plug to pin 2 (brown/red, signal for dimming up the mirror (when dimmed) as soon as the interior lighting is switched on when reversing)
Attach all cables additionally to the already existing cable.

Where is this control unit (left steered car):
The on-board control unit (J519) you can find at the outside of the driver's footwell.
You come there, but there is not much space available.
J519.jpg


J519_2.jpg


Kabelverlegung 0051.jpg

This picture is from the side, there is about the installation of a music system...

Removing hood opener (left steered car):
In order to clip out the footboard, the hood opener must first be removed.
The small ring must be clipped out with a screwdriver with the lever pulled from the right side behind the lever to the right.

Kabelverlegung 0052.jpg


Kabelverlegung 0048.jpg

This pictures are from the side, there is about the installation of a music system...

How to disassemble interior reading lamp:

1.jpg


2.jpg


3.jpg


4.jpg


5.jpg

This pictures are from the side...

I hope this helps you...
 
Last edited:
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Hussam

Active Member
Jan 6, 2019
15
0
England
Thank you so much for the amazing information. I will start once I receive the items.


I have one more question, The on-board control unit (J519) is it in the same location with the right hand drive side (UK)?

is the The on-board control unit (J519) near the fuses? because I guess its on the passenger side?


Regards,

Hussam
 

astaller

Active Member
Dec 20, 2018
24
3
Germany
I have just asked myself this question, no idea I do not know.
But you can take a picture, maybe we will see more.
 

zedlor

Active Member
Aug 24, 2017
291
122
Warrington
Will you be able to send a picture please?
I'm in work atm but the OBD port on right hand drive is on the right of the steering wheel underneath the pop out cubby hole thing. I'm presuming you need to take that out and what you're looking for is in there, I don't know much more than that...
 
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