Volvo V/S90 front seats retrofit/standalone.

[Liqwood]

I have tried putting +12V to Pin 1, 3 and 16  and GND to pin 6 which should be all the required places in regards to the schematics page 99, but they are still not working. 

Guess I will have to figure out if the canbus system send the seats a message to activate.

Have you check if the control buttons on the seat are getting voltage? 
In general the seat controller needs to send turn on LIN signal to the control buttons on the side.  I can send you all the CAN BUS messages of my S60 2019 once the knob is turned active then you can build an Ardeuno board to replicate those massages, one of them should turn the damn thing on.  You'll also need to add 120 ohm resistor to close the loop.

That would be amazing.  I have a ECU in my car that can send custom canbus messages so I was hoping I could use that for this purpose.

Very interested to see how this turns out my project is extremely similar, please post any updates you have.  Thanks!