C4 Grand Picasso rear cabin fans issue

[-Milan-]

Hello guys,

I have a 2009 C4 Grand Picasso Exclusive with (what I think) is a weird issue.
The rear cabin air fans (the ones underneath the driver and passenger seats) are not working. Lexia diagnostic tool doesn't see any issues or errors with them, it runs successfully through the tests of both rear left and right fans, but the car doesn't start or control them at all. Both B-pillar switches are illuminated. If the B-pillar switch for the fans is unplugged, Lexia shows an error code about it immediately. What are we missing here? We spent hours trying all the options we could think of, played with the driver's AC control panel but none of it helped. Has anyone encountered this issue before?

Thank you for the advice in advance.

[mickthemaverick]

I wasn't aware that there are fans under the seats. Are you sure they are not just vents fed from the front?

[-Milan-]

Yeah, they are fans. They take the air from the front and push it for the rear bench. It's a lot of work to get to them though.

EDIT: I hope the photos are visible now.

[myglaren]

Imgur images are not viewable in the UK but you can upload them directly to the forum.

There is a guide for that Here

[-Milan-]

The only thing that we found out of order is that the temperature sensors (inside temperature, for the air entering the cabin) show the value of 6000+ degrees Celsius. But the AC/heating works without any issue. Does anyone know where can I find these sensors?