Hyundai TUCSON Hybrid Owner's Manual page 245

Convenience features
WARNING
Even if your vehicle is equipped with
Rear Occupant Alert, always make sure
to check the rear seat before you leave
the vehicle.
Rear Occupant Alert may not operate
when:
Movement does not continue for
a certain period of time or the
movement is small.
The rear passenger is covered with
an object such as a blanket.
Always be cautious of the
passenger's safety as the detection
function and second alert may
not operate depending on the
surrounding environment and
certain conditions.
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