Smart Apartement Ventilation

Today the Sensair S8 from Aliexpress arrived. I have now drawn a housing for the sensor with another ESP8266 (Wemos D1 mini). The sensor gives me the CO2 value in ppm, with this value I control my ventilation.

Housing:

Now I have to write some code. After some thought, it would be best if I had the following control
options:
- set level 1
- set level 2
- set level 3
- ventilate for 30 minutes

I noticed that 100ms is not enough to press the button. With a value of 500 ms, pressing the keys works stable.

The following is the ventilation level 2 code as an example:

// STAGE 2
On stage2 do

  // 4 X CLICK DOWN
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0
  Pulse,14,1,500
  gpio,14,0

  // 2 X CLICK UP
  Pulse,12,1,500
  gpio,12,0
  Pulse,12,1,500
  gpio,12,0

  //RESETGPIO
  gpio,12,0
  gpio,13,0
  gpio,14,0

endon

Now I can integrate the whole thing into my smart home and control it as I like. Unfortunately, I
haven't received the VOC sensor from Aliexpress yet, so I have to wait with the VOC-controlled
ventilation.

Now I build the PCP. Left: DC-DC StepDown converter, top right: ESP8266 (Wemos D1 mini), bottom
right: SSR relay

Found, apparently the Renault Megane has installed the same cable for the airbag

Now I take a closer look at the original device. The panel buttons are connected to this ribbon cable. I measure out which pin is for which button. Now I have to find the same ribbon cable with connector on aliexpres...

Because I don't want to have an extra power supply, I check whether I already have direct current somewhere in the housing. I'm lucky, the original control is operated with 12V. 

That means I also have to use a DC-DC StepDown converter so that the ESP8266 can be supplied with 5V.

First, I drew the original housing so that I could put my own housing above where I would then install

my PCP with the ESP8266.