A3 2.0 TDi auxiliary coolant pump

[8bit]

A friend has a 58-plate A3 Sportback, 2.0 TDi. Not sure on specific engine code etc. but can find out in case it's relevant. It showed the check engine light at the weekend, I checked it and found it showing P261A, relating to the auxiliary coolant pump. Anyone able to tell me whereabouts on this car I'll find said pump and a rough idea of how much and what sort of work is involved in changing it?

Edit to add - is there a specific fuse protecting this pump that I should check as well?