These locks are intended to help prevent children from accidentally opening the rear doors. Use them on both rear doors whenever a child rides in the rear seat of the vehicle.
If you slide the child safety lock to the lock position before closing that door, the door cannot be opened from the inside.
The door can only be opened by pulling the outside handle.

Locking, Unlocking with Door-
Lock Knob
Doors and LocksSRS airbags
The SRS airbag system in the Subaru Solterra is engineered to deploy
during specific types of severe impacts that may otherwise cause serious harm to
vehicle occupants. These advanced airbags function in combination with seat belts
to significantly reduce the risk of fatal or severe injuries.
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Information Display Input/Output Check Mode
NOTE:
In this mode, it is possible to verify the items in the following chart.
Check Code Table
Check code
Check item
Related items
01
Information display
Multi information display
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Seat Belt Warning Beep
If the driver's seat belt is not fastened
when the ignition is switched ON, a beep
sound will be heard for about 6 seconds. If
the driver or the front passenger's seat belt
is not fastened and the vehicle is driven
at a speed faster than about 20 km/h (12
mph), a beep sound will be heard again ...