Cadillac 2004 DeVille Owner's Manual page 383

To reinstall the rear seat cushion, do the following:
CAUTION:
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A safety belt that isn't properly routed through
the seat cushion or is twisted won't provide the
protection needed in a crash. If the safetybelt
hasn't been routed through the seat cushion at
all, it won't be there to work for the next
passenger. The person sitting in that position
could be badly injured. After reinstalling the
seat cushion, always check to be sure that the
safety belts are properly routed and are not
twisted.
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