Chrysler PT Cruiser Owner's Manual page 86

84 THINGS TO KNOW BEFORE STARTING YOUR VEHICLE
WARNING!
A shoulder belt placed behind you will not protect
you from injury during a collision. You are more
likely to hit your head in a collision if you do not
wear your shoulder belt. The lap and shoulder belt
are meant to be used together.
Removing Slack From Belt
3. When the belt is long enough to fit, insert the latch
plate into the buckle until you hear a "click."