Volvo V/S90 front seats retrofit/standalone.

[kaptinkeiff]

Nope nothing. They are from a 2016 model,  they are in the first post in this thread.

Sorry for the delay in getting back to you, I finally found the wiring diagram that describes your seats

Yours appear to be the ones classified as "10A Passenger Seat Internal Harness High LHD"

I'm not sure why none of the other wiring diagrams show this un-canbussed passenger seat, but it matches with yours from what I can see.

There is only a lin bus connection to your seat...I presume the seat must be expecting a wake command from it, potentially?

The battery saver (pin 16?) no longer looks to exist, too, but pin 11 is the one used for the lin bus, I'm not sure if there are any easy tricks to get it live :/ 

Someone with a working passenger seat may need to record the lin command it's sent, unless there's some other way someone knows about? Really really annoying though, not sure why on earth it's like that!

The schematic file to find is called 

Aftermarket Wiring Diagrams CMA MY24
SJ1001860

I believe I found it from somewhere else on this forum, I downloaded quite a few before finding it.

No, you are not correct at all. 
With CMA modules,  the seat heating / ventilation module is embedded into the seat controller. 
The LIN you see in the diagram goes to the CCM and has nothing to do with the wakeup.  Check out page 1E_LIN_Comfort. 

The seat controller is a CAN BUS and a slave LIN slave unit. It wakes up with the can bus message from the CEM. 
Since the seat module has completely changed, most likely the CAN bus message for wake up has changed too. The messages I shared in this forum are from an SPA 2019 car.

Look at his plug, his seat does not have any CAN wires going to it? That's plug block 506. How can he provide it a wake up command?