Seat Belt Pre-Tensioners; Device Operation - Lotus Evora Service Notes

Lotus Service Notes
WARNING: Proper operation of the SRS system requires that the vehicle structure remains in its origi-
nal production configuration. Any damage to the SRS components and/or their respective mounting
brackets, including the chassis, requires replacement, not repair.
4. Fit the airbag module to the fascia panel and tighten the four M6 nuts to 10 Nm.
5. Fit a new airbag door to the fascia panel and tighten the two M6 nuts to 10 Nm. Ensure the 2 plastic barb
clips are correctly engaged.
6. Refit the fascia panels (see section VE) and plug in the passenger airbag harness connector.
7. When all service work is complete, check that the airbag tell tale lights for a few seconds with ignition, and
then goes out.
WF.12 - SEAT BELT PRE-TENSIONERS
WARNING:
• Failure to comply with the instructions, safety standards and operating procedures as described
in this section, may cause vehicle damage and/or personal injury.
• Both driver and passenger front seat belt assemblies must be replaced after SRS deployment. Do
not attempt to repair or reuse.

Device Operation

Initiated at the same time as the airbags, is a pyrotechnic device on each front seat belt reel assembly to
apply a tightening force to the belt reel and remove any slack from the belt. The force sustained by the belt and
its user during the event, is then controlled by a torsion bar within the belt reel to limit the deceleration force to
which the occupant is subjected. When airbag/pre-tensioner triggering conditions apply, the SDM signals igni-
tion of a gas generator on each front seat belt assembly, the pressure from which forces a train of balls around
a tubular track to apply a retraction force to the belt reel.
Section WF
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