Toyota PRIUS Manual page 221

 "PASSENGER AIR BAG" indicator information
If any of the following problems occur, it is possible that there is a malfunc-
tion in the system. Have the vehicle inspected by any authorized Toyota
dealer or repairer, or another duly qualified and equipped professional.
 Neither "ON" nor "OFF" comes on.
 The indicator light does not change when the airbag manual on-off switch
is switched to "ON" or "OFF".
CAUTION
 When installing a child restraint system
For safety reasons, always install the child restraint system in a rear seat. In
the event that the rear seat cannot be used, the front seat can be used as
long as the airbag manual on-off system is set to "OFF".
If the airbag manual on-off system is left on, the strong impact of the airbag
deployment (inflation) may cause serious injury or even death.
 When a child restraint system is not installed on the front passenger
seat
Ensure that the airbag manual on-off system is set to "ON".
If it is left off, the airbag may not deploy in the event of an accident, which
may result in serious injury or even death.
PRIUS PHV_OM_OM47831E_(EE)
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