On all models, as on most vehicles produced after 1990, a Supplemental Restraint System (SRS) air bag for the driver and front seat passenger is installed, which must protect the driver and front seat passenger from severe or fatal injury in the event of a frontal or front crash. This system consists of an electronic crash sensor installed on the center tunnel behind the instruments cluster, and two airbag assemblies installed on the steering wheel and the passenger side dash. For the 2002 model year, seat belt pre tensioners are featured; these remove slack from the seat belts during severe impacts. The driver side air bag is fitted in the steering wheel hub, the electrical signal triggers inflator assembly to release the air bag almost simultaneously. Located above the glove compartment is the somewhat larger passenger's side airbag and has a textured trim cover that separates when activated. The electronic crash sensor feeds power to the airbag system even if the battery power is switched off and monitors the system each time the car is started and the 'SRS' light will be on if everything is working well. During the servicing of some other parts anywhere near the SRS system it is necessary to turn it off in order to avoid the accidental deployment of the system. To disable the system the wheels should be rotated until they are parallel to the ground, the key should then be turned to the Lock position and the negative terminal of the battery should then be disconnected for at least 2 minutes in order to drain the backup power source. In the models produced from the year 2006, the airbag warning light is checked when all the accessories are switched off, the ignition switch is off and the ACM fuse is pulled out. Enabling the system requires reconnecting the ACM fuse and the battery cable and a test of the SAS system. If a person is required to work on an airbag module, the airbag opening must be directed away from his or her body; using electrical test equipment on any Airbag wiring or components is prohibited. Returning live airbag modules or seat belt pre-tensioners should be handed over to a certified repair centre for disposal. For replacement of the driver's side airbag module, and the clock spring assembly together with the passengers side airbag module, certain procedures are followed Entering the airbag system has to be disarmed and the airbag module accessed carefully.