[IainG]

Hi
VIda(software)Dice(hardware) is the volvo diagnostics system and covers a lot more than a generic code reader. Also has fault finding routines and tests.
On mine with Vida Dice, the alternator output is tested against specific test temperatures. ( this is the input the car gives to the alternator to control the voltage in conjunction the regulator in the alternator.)

Hence the correct alternator is required (that accepts this input, relative to temperature.)
I have changed the alternator on mine twice.
The original Volvo one was I believe a Denso unit. I just replaced with a Denso unit.
Volvo don't make alternators, they just put their name and markup on a "Denso" or other manufacturers unit.
They do run very hot and have to kick out 150 amps for quite a lot of their life especially on short winter journeys, and can be prone to fail.
The power steering pump is electric so can have a high draw on top of all the other things. Being a diesel the starter takes more the starter on a petrol car + lights +etc+ etc. Soon adds up.
Iain