2009 Cadillac STS-V Owner's Manual - Page 9

Head Restraints { CAUTION: Sitting in a reclined position when the vehicle is in motion can be dangerous. Even if when buckled up, the safety belts cannot do their job when reclined like this. The shoulder belt cannot do its job because it will not be against your body. Instead, it will be in front of you. In a crash, you could go into it, receiving neck or other injuries. The lap belt cannot do its job either. In a crash, the belt could go up over your abdomen. The belt forces would be there, not at your pelvic bones. This could cause serious internal injuries. For proper protection when the vehicle is in motion, have the seatback upright. Then sit well back in the seat and wear the safety belt properly. Do no have a seatback reclined if your vehicle is moving. Adjust the head restraint so that the top of the restraint is at the same height as the top of the occupant's head. This position reduces the chance of a neck injury in a crash. 1-5