Q: What does a seat belt pretensioner do?

asked by on December 14, 2015

What does a seat belt pretensioner do?

Seat belts are lifesaving devices, but technology has evolved beyond the point where these were just static belts that held you in place during an impact. Seat belt pretensioners are used on the driver and passenger front seat belts to help reduce the chance of injury. Here’s what they do:

  1. The pretensioner works with the seat belt retractor.

  2. The pretensioner will not automatically engage in all impacts (only certain types of impact).

  3. When deployed, smoke will come from the pretensioners. This is normal.

  4. The pretensioner is designed to tighten the belt during impact, but then allow the belt to release afterward.

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