I am assuming you have a 406.  Others have experience of the airbag problem,
I understand that it is a joint under the seat where the seatbelt
pretensioner connects in and most people seem to solder it.   I believe
there is a similar joint under each front seat and both can cause the
problem.    Mine were both done when still under warranty.

I have personal experience of the recirc motor.   It is accessible (but not
visible) when you remove the glove box (two hinge pins) and extract the
plate behind it.   You can also get to it by laying on your back in the
footwell and reaching up.   Before disconnecting the motor, make sure that
the flap is in the open position (you can see the flap if you remove the
grid and pollen filter underneath the passenger side windscreen wiper).
With the ignition on you can locate the motor behind the glove box by
feeling for the vibration, it is to the right of the hole behind the
glovebox.   Locate the wire coming from it and feel along to a large
connector.    It can be unplugged at this point but it is a bit of a fight
to get it out.   The problem with the motor is caused by the plastic gears
inside the unit stripping off teeth.   Some people have replaced the gears
with ones bought in model shops but I think the main problem is a small
electronic device which I suspect is supposed to detect the increased power
demand when the flap reaches the end of its travel and cut the power.

Let me guess... is it a 306?

WOW..... can't beleive how simple it was to fix the Airbag light. I been
driving around for 18 months with the damn thing on. Got under the drivers
seat, found 2 wires, fiddled/moved them a bit, but the light stayed on. Went
to passengers seat, found same orange wires, fiddled around, pulled
saquashed them a bit, light fixed!!! Should have done it ages ago.

Now for the recirc flap - had a quick look, but didn't see anything.......

Mal