SOWC Servo Piston Releases
WARNING: This page is about a different car, the 2020 Cadillac XT5. However, it is still accessible from the selected car via links, so may be relevant.
1 Reverse & 6-7-8-9 Solenoid
The 1 reverse & 6-7-8-9 solenoid energizes applying pressure against the 1 reverse & 6-7-8-9 regulator valve spring force. This blocks LINE fluid from entering the 1 REV/6789 FEED fluid circuit. 1 REV/6789 FEED fluid is routed to the EXHAUST BACFILL fluid circuit and thru orifice #20 into the EXHAUST fluid circuit.
SOWC Servo Piston
The SOWC servo piston is released. 1 REVERSE APPLY fluid is exhausted thru orifice #49 into the 1 REVERSE FD fluid circuit and directed thru the clutch select valve into the EXHAUST BACKFILL fluid circuit.