Belt tensioners
Belt tensioners |
The car is equipped with seat-belt tensioners for the front seats. A seat-belt tensioner tightens the seat belt in the event of a collision to reduce the forward movement of the occupant's body.
The seat-belt tensioner on the driver's side is connected to pins 8 and 9 of the SRS control module. The seat-belt tensioner on the passenger's side is connected to pins 15 and 45 of the same control module.
The cable carries test and detonation current from the SRS control module to the seat-belt tensioner.
The seat-belt tensioner consists of an explosive charge which is activated by the SRS control module together with the airbags. The seat-belt tensioners may also be activated separately in the event of a rear-end collision or a less severe head-on collision.
When the charge is detonated it generates a gas under high pressure which drives a piston in an aluminium tube. This piston is connected to the seat-belt reel via a steel wire. The distance travelled by the piston is the maximum length of seat belt that can be retracted and depends on the amount of slack in the belt.