EBD System
WARNING: This page is about a different car, the 1996 Volvo 850. However, it is still accessible from the selected car via links, so may be relevant.
EBD is integrated with ABS system and controls braking force to rear wheels. This ensures that vehicle brakes smoothly without activating ABS. EBD pressure sensor is connected to master cylinder primary circuit and indicates if primary circuit is under pressure. EBD replaces reducer valve which would otherwise reduce pressure in rear wheel brake circuit. Because EBD does not require as much brake fluid as ABS/TRACS, hydraulic pump is not activated.