Cadillac 2008 CTS Owner's Manual page 63

Driver Side shown, Passenger Side similar
The seat-mounted side impact airbags for the driver and
right front passenger are in the side of the seatbacks
closest to the door.
Driver Side shown, Passenger Side similar
The roof-rail airbags for the driver, right front passenger,
and second row outboard passengers are in the
ceiling above the side windows.
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