Fault symptoms
WARNING: This page is about a different car, the 2001 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.
The symptom for a short circuit to B+ is that the seat-belt warning lamp does not go on.
The symptom for an open circuit/short circuit to ground is that the seat-belt warning lamp is on constantly, irrespective of the seat-belt buckle switch.