Phil,

I've got the ISO scantool listed in your first link, and it works fine with
the HDi 138 in my Citroen C4.

You'll only get the data listed in to satisfy European emission regulations,
plus the fault codes. You will not be able to fiddle with any of the
multiplex settings, like how long the courtesy light stay lit, or how dark
it has to be before the auto head lights fire up, that's specific to PSA's
electronics.

Your vehicle is pre 2003. Diesel vehicles after 2003 must be ISO OBD ready,
so it's not certain that your car is compliant - however I'd bet that it is.

If your OBD connector has the ISO pins, it'll probably work:
http://www.auterraweb.com/obdiipinout.html
... and I suggest you get a copy of OBD-II ScanMaster demo from
http://www.wgsoft.de/

FYI, the OBD socket in my Citroen in hidden behind the ashtray, so if you've
not found it yet, it's a regulation requirement for it to be located within
1m of the drivers seat.

Chris