As vehicle speed increases and operating conditions become appropriate, the PCM energized the 2-3 shift solenoid valve in order to shift the transmission into Third gear. The manual valve remains in the Overdrive (D) position, and line pressure continues to feed the drive and the PRND4 fluid circuits.
The PCM energizes the normally open 2-3 shift solenoid valve, which blocks the 2-3 signal fluid from exhausting. The 2-3 signal fluid pressure is routed to both of the 1-2 and 2-3 shift valves.
The 2-3 signal fluid pressure moves the valve against a spring force in order to initiate the 2-3 upshift. The 2-3 drive fluid is routed through the valve and into the 3-4 drive fluid circuit.
The 3-4 drive fluid pressure seats the #5 checkball, and 3-4 drive fluid is forced through the #26 orifice and into the direct clutch feed fluid circuit. The #26 orifice helps to control the direct clutch apply.
The direct clutch fluid pressure applies the direct clutch, causing the transmission to shifts into Third gear.
The 3-4 drive fluid is also routed to the 3-4 shift valve in preparation for a 3-4 upshift.
Direct clutch feed fluid is also routed to the 2-3 accumulator piston. This fluid pressure moves the piston against a combination of spring force and the 2-3 accumulator feed fluid pressure. This action absorbs the initial direct clutch fluid pressure in order to cushion the direct clutch apply. the movement of the 2-3 accumulator piston forces some of the fluid out of the accumulator.
Torque Converter Clutch (TCC) Under normal operating conditions the TCC is released in Third gear. However the TCC apply could vary depending upon the vehicle application, and the TCC may be calibrated in order to apply in Overdrive Range - Third gear.
Release fluid pressure routed to the TFP Val. Position Sw. Assembly signals to the PCM that the TCC is released.
As vehicle speed increases and operating conditions become appropriate, the PCM energized the 2-3 shift solenoid valve in order to shift the transmission into Third gear. The manual valve remains in the Overdrive (D) position, and line pressure continues to feed the drive and the PRND4 fluid circuits.
Under certain conditions the hybrid vehicles engine will shut off and the electric auxiliary transmission fluid pump will start running to keep the transmission pressurized and ready for the engine restart. This engine off condition is a fuel economy feature and the L4 hybrid transmission's electric auxiliary fluid pump is an enabling component.
The PCM energizes the normally open 2-3 shift solenoid valve, which blocks the 2-3 signal fluid from exhausting. The 2-3 signal fluid pressure is routed to both of the 1-2 and 2-3 shift valves.
The 2-3 signal fluid pressure moves the valve against a spring force in order to initiate the 2-3 upshift. The 2-3 drive fluid is routed through the valve and into the 3-4 drive fluid circuit.
The 3-4 drive fluid pressure seats the #5 checkball, and 3-4 drive fluid is forced through the #26 orifice and into the direct clutch feed fluid circuit. the #26 orifice helps to control the direct clutch apply.
The direct clutch fluid pressure applies the direct clutch, causing the transmission to shifts into Third gear.
The 3-4 drive fluid is also routed to the 3-4 shift valve in preparation for a 3-4 upshift.
Direct clutch feed fluid is also routed to the 2-3 accumulator piston. This fluid pressure moves the piston against a combination of spring force and the 2-3 accumulator feed fluid pressure. This action absorbs the initial direct clutch fluid pressure in order to cushion the direct clutch apply. the movement of the 2-3 accumulator piston forces some of the fluid out of the accumulator.
Torque Converter Clutch (TCC) Under normal operating conditions the TCC is released in Third gear. However the TCC apply could vary depending upon the vehicle application, and the TCC may be calibrated in order to apply in Overdrive Range - Third gear.
Release fluid pressure routed to the TFP Val. Position Sw. Assembly signals to the PCM that the TCC is released.