Volvo 2008 V70 Owner's Manual page 32

Convertible child seats should be installed in the rear seat only.
A rear-facing convertible seat should not be positioned behind the driver's seat unless there is adequate space for
safe installation.
39
01 Safety
Convertible seats
3. Fasten the seat belt by inserting the latch plate into the buckle (lock) until a distinct click is audible.
4. Pull the shoulder section of the seat belt out as far as possible to activate the belt's automatic locking function.
5. Press the convertible seat firmly in place, let the seat belt retract and pull it taut. A sound from the seat belt
retractor's automatic locking function will be audible at this time and is normal. The seat belt should now be locked in
place.
NOTE
The locking retractor will automatically release when the seat belt is unbuckled and allowed to retract fully.
6. Push and pull the convertible seat to ensure that it is held securely in place by the seat belt.
WARNING
It should not be possible to move the child restraint more than 1 in. (2.5 cm) in any direction.
The convertible seat can be removed by unbuckling the seat belt and letting it retract completely.