Here is the photo of parts (cable connectors 4D0971636 still on the way)

I am gonna start with pads installation. With seats removed, cables under carpet will be more accessible.

 

Seat base completed

1. Pop up seat from grey brackets
2. Remove clips in the middle and sides
3. Try and align heat pad
4. Mark holes a cut it carefully
5. Apply glue on seat and pad also
6. Install pad a put wire through the hole in the base (which is already there)
7. Align cover and install claps

 

Here how looks completed base

 

Backrest completed

 

2nd seat completed
note: dont take off whole cover, just a part. This also applies for backrest where is belt. Dont take off plastic cover on top, where belt is going out.

 

Wiring completed

• I installed wire on left side, so label "right side" on cable is mistake (it is left side)
• You need to take apart:
  • Pillar B and C
  • Back seats
  • Driver seat
  • Back of center console

When you have clean space, put wires under carpet and plastics. Place control unit inside center console and attach it to the frame, so It wont make noises.

 

Put 2 red wires (Battery and ACC wire) to fuse box.

• 10A for Battery wire (you can cut out fuse that came already with heating pads)
  • 1mm or 1,5mm cable is recommended
• 5A for ACC wire

Negative wire (black) attach to pillar B.
Light wire (orange) attach to grey wire that goes to air flaps wheels.

 

During installation I have found out 2 things:

1. OEM switches are not working properly (changing levels) without tweaking
That chinese control/switches are working together with High/Low signal (5V / 0V) -> this means logical 1/ logical 0. So when you pressed chinese button, it goes to 0V and then it swich level of heating. You need to measure leftover voltage in circuit (bettween black and brown cable). Mine OEM swithes were leaving 2.4V and 3.8V after pressing. Resistors are the only option.

I have measured 1.07mA current in circuit. That means R=V / I => R=2.4V / 0.00107A so result is 2242 Ohm. I have used 5kOhm resistors, to pull down signal to 0V.
What now? Solder resistor between black and brown cable on each switch. This is important to get buttons working!

2. OEM switches are showing leves in the same direction

• Left button: 3 2 1 direction
• Right button: 3 2 1 direction

This looks weird, so to get buttons mirrored like this:

• Left button 3 2 1 direction
• Right button 1 2 3 direction

I have swapped LED Stage1 (white) and LED Stage3 (blue) to this wiring:

• LED Stage 1 => blue
• LED Stage 3 => white

If you have any questions, please contact me or write it here.

Use this MOD at your own risk! I am not responsible for any damage that you cause to your car.

 

Awsome mod! Nice work!

 

Thanks man

 

I was thinking going the same route as you, since i bought the car. And now you made it easier for me. Thanks!

 

The most tricky part is removing covers. Please note that OEM heating pads are sewed into cover, so additionally installed heating pads are heating slower than original.
But it costs much less than replacing covers.

 

Thanks for the write-up. How do you know that OEM heating pads are sewed into covers?
I see that the pads have their own part numbers, independently from the covers.

 

Because I wanted to make custom alcantara covers for seats, so I disassembled front passenger seat to check how its done. Seat cushion is clean and seat heating is included in the seat cover.

 

Got it. Thanks. Yes, it looks that for some types of covers, the heating mat is a part of the cover. It depends on the PR code. N0C, N1P, N2Z, N4M, and N5E - heating mat is integrated, for other PR codes, there are separate partnumbers for the mats. I am N1P unfortunately, but I'm wondering if retrofitting OEM mats would still be possible. I suspect I can just glue them to the pad the way you did it.

I would prefer retrofitting OEM mats because they also cover bolsters:

Was there any reason why you didn't decide to use the OEM controller? Integrating with the OEM switches would have been easier.
Thanks for the write-up again, and the pictures. It will be much easier with them now.

 

Do you mean rear climatronic unit? Rear climatronic has to be connected with front and it would be throwing errors all the time. I have used OEM buttons with non-oem heating pads and controller. Tricky part was only to get buttons working, but from there is pretty easy. Other version with rear climatronic would be nightmare...just waste of time and money.

 

Hi, that's not what I meant. There are three major configurations:

• 2-zone climatronic
• 2-zone clima + rear seat heating
• 4-zone clima (with rear seat heating)

You converted "2-zone clima" to "2-zone clima + rear seat heating". You used a 3rd party heating mats, and 3rd party controller, while there is an OEM controller for rear seat heating. It is 3AA-959-772 (designation J786), and is mounted behind the glove box:

It interfaces directly with the OEM buttons, which you have installed:

I'm guessing the controller could be fitted where you placed the 3rd party controller for easier installation. It looks that it's a simple controller, with no CAN connection. It only interfaces with the buttons, and the heating mats.
I don't think there's any actual benefit from using one or another. They both probably do the same thing. There would have been less work with interfacing the buttons if you had used the OEM one, but apart from that I think it's fine.

 

Yeah, I knew about it, but I did not want to buy another controller when I already had one. If that chinese unit fails, then I will replace it with original one.