Shift Pressure Relay Valve
WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.
S5 signal (18) fluid is routed to the shift pressure relay valve and applies the valve against spring force.
Exhausting low and reverse clutch (24) fluid is routed into the B5 control 2 (38) fluid passage at the M1 shift valve, the B5 control 1 (37) fluid passage at the solenoid relay valve, the reverse control (25) fluid passage at the B5 control valve, and on to the shift pressure relay valve where it exhausts.