Selective bypass of solenoid-controlled supply to friction elements of an automatic transmission

A system for controlling engagement and disengagement of a friction element, comprising:

• a source of line pressure;
• a source of exhaust pressure;
• a manual valve including a chamber hydraulically connected to the exhaust pressure source and line pressure source, a spool moveable in the chamber between a forward state and a reverse state including
• a first land for opening communication to the exhaust pressure source through the manual valve in the forward state and for closing said communication in the reverse state,
• a second land for opening communication to the line pressure source through a first outlet of the manual valve in the reverse state and for closing said communication through the first outlet in the forward state;
• a friction element communicating with the line pressure source through a hydraulic path that includes the manual valve and no other valve;
• and
• a control valve including a port communicating with the friction element, the control valve producing control pressure at the port when the manual valve is in the forward state.