940 SE L4-2320cc 2.3L SOHC Turbo VIN 87 B230FT (1991)
Seat Belt Tensioner: Description and Operation
Seat Belt Tensioners
The front seat belts are equipped with seat belt tensioners as part of the SRS system. In a collision, the tensioners tighten the seat belts instantly to take
up any slack.
The seat belt tensioners are incorporated into the B-post seat belt reel.
On impact a charge is detonated by the crash sensor. The charge forces the piston through a cylinder, pulling a cable which tightens the seat belt.