Removing the relay box
WARNING: This page does not describe the selected car, but rather 8 other vehicles, including the 2006 Volvo S80, 2005 Volvo S80, 2004 Volvo S80, 2003 Volvo S80, and 2002 Volvo S80. However, it is still accessible from the selected car via links, so may be relevant.
Insert a screwdriver between the bracket and the relay box. Turn the screwdriver so that the bracket opens out. At the same time, pull the relay box out of the bracket towards the underside of the dashboard. Lift the relay box off the bracket. Pull the relay box downward under the dashboard.