Reading off the control module identification
WARNING: This page is about a different car, the 2004 Volvo S40, 2003 Volvo S40, 2002 Volvo S40, 2001 Volvo S40, and 2000 Volvo S40. However, it is still accessible from the selected car via links, so may be relevant.
VIDA identifies the control module by reading a code from the memory of the module. This code contains information about the control module P/N.