Phase 2
WARNING: This page is about a different car, the 2001 Saab 9-3. However, it is still accessible from the selected car via links, so may be relevant.
The outlet valve opens, at the same time opening the passage from the caliper to the hydraulic accumulator, which quickly receives the pressure from the caliper. At the instant that the outlet valve opens, the control module starts the return pump which pumps the fluid back to the master cylinder. The wheel will now rotate faster.