How to Troubleshoot a GMC Seat Belt Retractor

1). Pull the top portion of the seat belt using quick tugs. Many GMC vehicles feature an auto-locking mechanism built inside the retractor that locks the seat belt from movement in the case of an accident or an abrupt stop.
2). Place a screwdriver or other flat-ended object into the bottom of the retractor. A seat belt may get twisted and caught up in the retractor preventing it from working properly. Poke the screw driver into the retractor to straighten out and untangle a stuck seat belt.
3). Take your GMC vehicle into an authorized GMC mechanic to have it serviced. Pretensioners are hidden mechanisms inside the retractor that cannot be seen and are only activated during a crash or high-impact stop. The pretensioners tighten and lock the seat belt to prevent injury. If the pretensioners have been activated, they need to be replaced by a trained mechanic.