What does your car seat belt pretensioner do?

Your seat belt pretensioner is one of the vital safety mechanisms in your car. In the case of a crash, it holds you firmly in your seat and allows you to come into contact with an airbag in a controlled manner. While a normal seat belt just locks, pretensioned seat belts pull you back into your seat during a crash and set your body up for the airbag.  A few milliseconds later it releases and allows you to come into contact with the airbag at the correct time. Most pretensioners are only designed to be used once and in the event of a crash, the whole seat belt mechanism will need to be replaced. Find out more about the pretension and non-pretension seat belts here.

Seat belt pretensioner

The difference between electric pretensioner, mechanical and pyrotechnic pretensioners.

The Mechanical pretensioner– The mechanical pretensioner is a pendulum that locks into place between internal gears inside the pretensioner during deceleration and traps the belt to keep you from moving forward. Mechanical pretensioners are the reason for the seat belt locking when you pull on the seat belt quickly.

The electric pretensioner– The electric pretensioner replaces the pendulum with an electric sensor. This prevents the false locking condition commonly observed with the mechanical pretensioner. The electric pretensioner can interconnect with other parts of the car such as car rollover or airbag sensors. This can ensure that the seat belt will lock even if the deceleration is not enough to trigger the lock.

The pyrotechnic pretensioner– The pyrotechnic pretensioner is the most common type of pretension. This locks the seat belt in place and also takes up the slack that might be present therefore minimizing the movement of the occupant during a crash. It is the fastest of the three methods but the downside is that if it is triggered it must be replaced.


Why has your pretensioner failed a Warrant of Fitness (WOF)?

If your airbag light is on and a diagnostic scan shows there is a fault code for the pretensioner(s) then you will have to have it repaired or replaced to pass your WOF and keep you and your passenger/family safe. PLEASE NOTE: WE CAN ALSO ORGANISE RE-WEBBING OF SEAT / SAFETY BELTS FOR YOU, TO WARRANT OF FITNESS COMPLIANCE STANDARDS!


Seat belt pretensioner replacement

Is your seat belt pretensioner not locking or causing your Airbag / SRS light to come on the dash? If so, we can help! At Grimmer Motors, our team of talented mechanics can quickly identify the cause of a faulty pretensioner. From there, you can expect our professional team to get you and your car back safely on the road. PLEASE NOTE: WE CAN ALSO ORGANISE RE-WEBBING OF SEAT / SAFETY BELTS FOR YOU, TO WARRANT OF FITNESS COMPLIANCE STANDARDS!

We also offer repairs for Seatbelts not retracting, faulty seat belts, and more.

For the best seat belt pretensioner replacement services in Hamilton, contact Grimmer Motors today!


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