Volvo - is auto-locking possible? - Martin Wall
Does anybody know if the Volvo V70 (2000 on) can be set to auto-lock the doors above a certain speed? If so, how?
Volvo - is auto-locking possible? - SjB {P}
Yes.

I'll now describe in full because in my case it took some pursuading of the dealer for them to believe that it was possible, and I've heard that this is not unusual:

For any P2 platform Volvo:

1) Connect car to VADIS (Volvo After Sales Diagnostic and Information System)
2) Enter vehicle ID
3) Open Information Manager section
4) Select Group 3
5) Select Parts Catalogue
6) Select Section 34 / software page
7) Select part number as below

To activate:
S60 8637 412-1
S80 8637 408-9
V70 8637 410-5

To deactivate:
S60 8637 413-9
S80 8637 409-7
V70 8637 411-3

Cost is typically ten to twenty quid.
Volvo - is auto-locking possible? - Martin Wall
Many thanks!
Volvo - is auto-locking possible? - SjB {P}
No worries, Martin.

FYI, so it is no surprise if you get this software option applied: The doors and boot will all lock at about six mph, and remain locked until you manually unlock them or press the central locking button on the driver's door panel. i.e. they don't auto-unlock when the engine is turned off or the key is removed from the tumbler.

If you ever want to use the 'boot/tailgate only' release button on the remote fob to just open the boot or tailgate, whilst leaving other doors locked, remember that you have to press it twice within a couple of seconds. This is to ensure that a conscious command to use it was made.