Xantia electrics - KB
As s**s law would dictate in this cold weather, the heater fan for the passenger compartment has given up the ghost along with the rear screen demister.
I've tested the fan which works fine, so it can't be that, so therefore resorted to stripping the dashboard out to see if there was a loose connection as the fan sometimes worked, sometimes didn't. It has completely stopped now.

Has anyone had experience of this? Or is there a common link between the rear screen demister (switch) not working and the fan not working as both of them stopped at the same time. I have checked the fuses which are fine. I'm not sure either if they are on the same circuit, so if one stopped, the other may do too.
Xantia electrics - Andy22
my 406 rear windscreen demister doesn't work any more the fans at body height are working but i've never noticed any heat coming from the ones that are supposed to warm you legs and feet.

could this be linked too?
Xantia electrics - NVH
Re the fan.
If the fan is very weak or not working check the air con fluid level first. There is a tiny sight-glass on top of the reservoir.
Handbook will show where it is: on the 1.9TD on the LHS seen from the front.
If the aircon fluid is zero,there will also be very little resistance from the sliding controls.

Speaking from very recent experience !