Fluid Pressure Directed in Preparation for a Shift
VFS Line Solenoid
VFS line solenoid is energized allowing RANGE FEED fluid to enter the LINE VFS fluid circuit. LINE VFS fluid is routed to the ETRS mode enable valve.
ETRS Mode Enable Valve
LINE VFS fluid is routed to the ETRS mode enable valve applying pressure against ETRS mode enable valve spring force. This allows LINE fluid to be directed into the RANGE FEED fluid circuit. RANGE FEED fluid is then directed to the mode 1 ETRS valve.
Mode 1 ETRS Valve
RANGE FEED fluid is routed to the mode 1 ETRS valve and into the FEED 0 fluid circuit.
Mode 2 ETRS Valve
FEED 0 fluid is routed to the mode 2 ETRS valve and into the PARK ON fluid circuit. PARK ON fluid is directed to the ball check valve #14 and #15.
Ball Check Valve #14
PARK ON fluid is routed to the ball check valve #14. The ball check valve is seated by PARK ON fluid pressure.
Ball Check Valve #15
PARK ON fluid is routed to the ball check valve #15 applying pressure against the ball check valve spring force.
Park Release Servo Piston
PARK ON fluid is directed past ball check valve #15 and into the park release servo piston assisting with park release servo piston spring force to keep park engaged.
1 Reverse & 6789 Regulator Valve
The 1 Reverse and 6-7-8-9 solenoid is energized which applies pressure against the 1 Reverse and 6-7-8-9 Regulator Valve spring force. This allows LINE fluid to be blocked from entering the 1 REV/6789 FEED fluid circuit.