EVT Mode High - From Drive Range 4th Gear

EVT Mode High - From Drive Range 4th Gear

EVT Mode High is used to maximize engine efficiency and fuel economy under most normal driving conditions. The TCM processes input signals from the output speed sensor, the TP sensor and other vehicle sensors to determine the precise moment to command OFF the shift solenoid 2 and the normally high pressure control solenoid 3 trim, and shift the transmission into EVT Mode High.

4th Clutch Releases

Pressure Control (PC) Solenoid 3 Trim

The PC solenoid 3 trim is commanded OFF, allowing PCS 3 signal fluid to exhaust from the variable low and 1-2 reverse and 4th clutch regulator valve; the variable low and 1-2 reverse and 4th boost valve; and the shift solenoid valve - mode B.

Shift Solenoid 2

The shift solenoid 2 is commanded OFF, allowing solenoid 2 signal fluid to exhaust from the shift solenoid valve - mode A, the variable hi and 2-3-4 clutch regulator valve, and the 1-3 reverse clutch regulator valve.

4th Clutch Assembly

4th clutch fluid pressure exhausts through the case cover assembly, allowing 4th clutch spring force to move the 4th clutch piston and release the 4th clutch plates.

Shift Solenoid Valve - Mode A

Shift solenoid valve - mode A spring force moves the shift solenoid valve - mode A to the released position, allowing 4th clutch fluid pressure to exhaust through the valve into the exhaust backfill circuit. 234 clutch feed fluid pressure also exhausts through the valve.

Variable Low and 1-2 Reverse and 4th Clutch Boost Valve

Variable low and 1-2 reverse and 4th clutch boost valve spring force moves the variable low and 1-2 reverse and 4th clutch boost valve to the released position, allowing VL 12 reverse/4th clutch feedback fluid pressure to exhaust into the VL 12 reverse/4th clutch feed circuit.

Variable Low and 1-2 Reverse and 4th Clutch Regulator Valve

Variable low and 1-2 reverse and 4th clutch regulator valve spring force moves the variable low and 1-2 reverse and 4th clutch regulator valve to the released position, allowing VL 12 reverse/4th clutch feed pressure to exhaust through the valve into the exhaust backfill circuit.

Shift Solenoid Valve - Mode B

Exhausting 4th clutch/B cooling feed fluid pressure is routed to the shift solenoid valve - mode B, where it passes through the valve into the VL 12 reverse/4th clutch feed circuit.

Transmission Fluid Temperature (TFT) Sensor

Fluid pressure in the exhaust backfill circuit exhausts at the TFT sensor.

#3 Pressure Switch

With the actuator feed limit/backfill passage closed at the shift solenoid valve - mode A, actuator feed limit/backfill fluid pressure increases to actuator feed limit pressure. PS3 fluid pressure, fed by actuator feed limit/backfill pressure through the variable hi and 2-3-4 clutch regulator valve, also increases. PS3 fluid opens the normally closed #3 pressure switch, signaling the TCM that the transmission is in EVT Mode High.

#5 Pressure Switch

Actuator feed limit fluid passes through the variable low and 1-2 reverse and 4th clutch regulator valve into the PS5 fluid passage. PS5 fluid opens the normally closed #5 pressure switch, signaling the TCM that the transmission is in EVT Mode High.

#1 Pressure Switch

Actuator feed limit/backfill fluid pressure passes through the 1-3 reverse clutch regulator valve into the PS1 fluid passage. PS1 fluid opens the normally closed #1 pressure switch, signaling the TCM that the transmission is in EVT Mode High.

Shift Accumulation

4th Clutch Accumulator

4th clutch fluid also exhausts from the 4th clutch accumulator assembly. Accumulator spring force moves the 4th clutch accumulator piston to the released position.

EVT Mode High - From Drive Range 4th Gear