GM Service Manual Online
For 1990-2009 cars only
  1. Inspect all seat belt anchor bolts and the screws in order to verify that they are secure.
  2. Inspect the seat belt buckle. The buckle must lock and unlock easily.
  3. After inserting the latch into the buckle, tug sharply on the belt. The buckle must remain locked.
  4. Fully extend the shoulder belt portion to make sure that there is no twisting or tears in the belt.
  5. Let the shoulder belt retract fully. The belt should retract easily.