Manual Description
A warning chime also sounds for up to 6 seconds if the driver's safety belt is not buckled. The warning light and the chime go out when both driver and front passenger have bucked their safety belts. If the driver and front seat passenger do not both fasten their safety belts within about 24 seconds after the chime stops and the vehicle is moving at a speed of more than about 15 mph (25 km/h), the chime will again sound for about 6 seconds, then go off for about 24 seconds, then sound again for about another 6 seconds.
The same thing happens if one of the safety belts is fastened and then unfastened while the vehicle is moving. If your speed doubles (for example, from 15 mph to 30 mph – 25 km/h to 50 km/h), the energy increases 4 times! Because the occupants of the vehicle in the above example are not using safety belts, they are not attached” to the vehicle. In a frontal collision, they will keep moving at the same speed the vehicle was moving just before the crash, until something stops them - here, the inside of the passenger compartment.
Because the occupants of the vehicle in the example are not wearing safety belts, their entire kinetic energy will be absorbed by impact with the wall ⇒fig. The same principles apply to people in a vehicle that is in a frontal collision on the highway. Even at city speeds of 20–30 mph (30–50 km/h), the forces acting on the body can reach one ton (2,000 lbs or 1,000 kg) or more.
Manual Cover
General