Installing heated seats

[Andytech3]

During the winter break, while I was waiting for parts for my battery that was removed from the car, I decided to install heated seats that I simply missed in that car. But since the seats are very elegant, covered with leatherette, a heated pad mounted on the seat that connects to the 12V socket was out of the question
So I ordered this 100W set from Aliexpress for about 30€.

Part One: SEAT UPGRADE

The seats in the car are held on by 4 screws. After removing them, the first thing you need to do is remove all the plastic from the seat. The side lever has 2 Phillips screws hidden under the ZD logo.

The plastic is still held in place by 2 plastic pins that need to be pressed to slide out.

The cover fabric simply snaps out on the sides

The fabric is still attached from the bottom and back with a twisted piece of hard wire, just "open" it with pliers.

Then you can remove the entire bottom of the seat and pull off the cover, which is still attached to the foam at the seams with Velcro.

First, reflective stickers are glued to the foam so that they reflect the heat upwards as much as possible and the foam does not absorb it unnecessarily. Then, you need to make a hole in the middle of the back fold through which you can bring the cable out from under the foam. I made the hole with the tip of a micro-soldering iron. Then, you need to remove the Velcro from the front groove, stick the heating element nicely over the groove so that it fits (the heating element has a self-adhesive layer of glue on it) and then glue the Velcro back into the groove on the heating pad with chemoprene (don't overdo it with the chemoprene)

The procedure for the upper part of the seat is exactly the same, so I won't go into detail and will just add a few photos.

Part Two: ELECTRONICS ASSEMBLY

I dismantle the center tunnel in the car by unscrewing all the self-tapping screws around its perimeter. Then I need to disconnect the bowden cable for opening the rear trunk and then the connectors from the window control.

In the back I drilled a hole of the required diameter as well as the seat heating control and with a thin file I made a groove to prevent the control from turning. From the bottom, the same shape needs to be cut with a scalpel into the dust rubber from the handbrake. We can install the control.

I mounted the power module under the handbrake so that it wouldn't interfere with the center tunnel. I made the GND or minus pole of the heater from an unused hole under the tunnel (DO NOT FORGET to sand the paint down to bare metal! otherwise it will work poorly or not at all).

Then we will lead the cables for the heated pads out of the tunnel on the sides (and we will not confuse which cables belong to the left and which to the right seat ). We will install the seats back into the car and connect both connectors. ALMOST done.

There are still 4 wires coming from the wiring. Black is GND, so we already have the minus connected. Next comes out of it a Red cable with a fuse holder at the end, it is the Battery (permanent) +12V, it is connected directly to the +pole of the battery. Next there is another red wire (a bit confusing) but it no longer has a fuse holder on it, it is the key +12V (voltage comes there after turning the key to the ACC position). The last wire is yellow, it is +12V from the button backlight (there +12V appears after turning on the external outline lights).

The heater has a declared power of 100W, the on-board voltage is always around +12V (+/- 2V). 100/12 = 8.33 Amps is the maximum possible consumption, which means that we put a 10A fuse (red) in the fuse box.