Cadillac 2005 CTS Owner's Manual page 29

2. Push the latch plate into the buckle until it clicks.
If the belt stops before it reaches the buckle, tilt the
latch plate and keep pulling until you can buckle it.
Pull up on the latch plate to make sure it is secure.
If the belt is not long enough, see Safety Belt
Extender on page 1-27 .
Make sure the release button on the buckle is
positioned so you would be able to unbuckle
the safety belt quickly if you ever had to.
3. To make the lap belt part tight, pull down on
the buckle end of the belt as you pull up on
the shoulder part.
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