McLaren P1 Owner's Handbook Manual page 26

BEFORE YOU DRIVE
OCCUPANT SAFETY
Occupant Classification System - Front
Passenger's Seat
The system can determine if the passenger's
seat is occupied using a capacitance mat
fitted in the seat base, and by checking the
seat belt buckle engagement on the
passenger's seat belt. The passenger's front
air bag will not be active unless a specific
weight is exceeded. This allows child restraint
systems to be used on the passenger's seat.
1.20
The status of the air bags is indicated by the
PASSENGER AIR BAG OFF warning light on the
overhead console.
The PASSENGER AIR BAG OFF warning light
illuminates when the ignition is switched on
and extinguishes after 5 seconds.
The warning light will remain illuminated if the
passenger's seat is unoccupied or if a child
seat is fitted.
NOTE: The PASSENGER AIR BAG OFF
warning light is always illuminated unless
the specific weight is exceeded.
If the PASSENGER AIR BAG OFF warning light
is illuminated, the passenger's front air bag is
not active. However, the side head air bag and
the belt tensioner on the passenger's side
remain active even if the PASSENGER AIR BAG
OFF warning light is illuminated.
WARNING: If the PASSENGER AIR BAG
OFF warning light is not illuminated
when the child seat is fitted, the front air
bag is still active. The child could be
seriously injured if the passenger's air
bag inflates.
WARNING: To ensure that the occupant
classification system functions correctly,
never place objects under the seat. Also
never apply additional material such as a
blanket, cushion, or aftermarket
equipment such as a seat cover, heater,
or massager. These items can seriously
affect how well the occupant
classification system operates. McLaren
recommends that aftermarket
equipment such as covers, heaters, and
massagers are NOT used.