Park - Engine Running

Park (Engine Running):

PARK - (Engine Running)

When the gear selector lever is in the Park (P) position and the engine is running, fluid is drawn into the oil pump and line pressure is directed to the pressure regulator valve.

PRESSURE REGULATION

Pressure Regulator Valve: Regulates pump output (line pressure) in response to torque signal fluid pressure acting on the boost valve, spring force, and line pressure acting on the end of the valve. Line pressure is directed to the manual valve, both accumulator valves, torque signal regulator valve, Torque Converter Clutch (TCC) regulated apply valve, the temperature sensor in the pressure switch assembly (PSA) and the actuator feed limit valve. Also, line pressure feeds the converter feed fluid circuit through the pressure regulator valve.

Actuator Feed Limit (AFL) Valve: Line pressure is routed through the valve and into the actuator feed fluid circuit. The valve limits actuator feed fluid pressure to a maximum pressure. Actuator feed fluid is routed to the pressure control solenoid, each of the shift valves, and also feeds the 1-2 signal and 2-3 signal fluid circuits.

Pressure Control Solenoid (PCS): Controlled by the PCM, the PCS regulates filtered actuator feed fluid pressure acting on the end of the torque signal regulating valve.

Torque Signal Regulating Valve: Regulates line pressure into the torque signal fluid circuit. This regulation is controlled by filtered actuator feed fluid pressure from the PCS. Torque signal fluid pressure is routed to the accumulator valves and the boost valve to control shift feel.


LO/REVERSE BAND APPLIES

Manual Valve: Mechanically controlled by the gear selector lever, the manual valve is in the Park (P) position and directs line pressure into the PRND4 and PRN fluid circuits.

Pressure Switch Assembly (PSA): PRND4 fluid is routed to the PRND4 fluid pressure switch in the PSA and the PSA signals the PCM that the transaxle is in the Park (P) position. Also, line pressure is routed to the temperature sensor in the PSA.

1-2 Shift Solenoid: Energized by the PCM, the normally open 1-2 shift solenoid is ON and blocks 1-2 signal fluid from exhausting. 1-2 Signal fluid pressure acts on the 1-2 and 3-4 shift valves.

1-2 Shift Valve: 1-2 Signal fluid pressure holds the valve in the downshifted position against spring force. Lo/PRN fluid is routed through the 1-2 shift valve and into the lo band fluid circuit.

Lo & Reverse Servo: Lo band fluid is routed to the inner area of the servo piston. Lo band fluid pressure moves the servo piston and pin assembly against spring force to apply the lo/reverse band.

2-3 Shift Solenoid: The normally open 2-3 shift solenoid is OFF and 2-3 signal fluid is exhausted through the solenoid.

2-3 Shift Valve: Spring force holds the 2-3 shift valve in the downshifted position.

3-4 Shift Valve: 1-2 Signal fluid pressure holds the 3-4 shift valve against spring force in the First and Fourth gear position.

Lube 2: The lube 2 fluid circuit is fed by line pressure at the pressure regulator valve. Lube 2 fluid is routed through the oil feed pipes and into the forward clutch support. Lube 2 fluid provides lubrication in the rear of the transaxle.


SHIFT ACCUMULATION

1-2/3-4 and 2-3 Accumulator Valves: Line pressure is regulated into accumulator fluid pressure. This regulation is basically controlled by torque signal fluid pressure acting on the end of the valve.

1-2, 2-3 and 3-4 Accumulator Assemblies: Accumulator fluid is routed to each of the accumulator assemblies in preparation for upshifts. The fluid routed to the 1-2 and 34 accumulators is orificed by the #4 and #7 checkballs. The 2-3 accumulator fluid circuit does not use a checkball to orifice accumulator fluid to the 2-3 accumulator.


TORQUE CONVERTER / COOLER and LUBE CIRCUITS

Refer to Reverse (R) range for a complete description of these circuits.


Note: Actuator feed fluid continues to feed the 2-3 signal fluid circuit through orifice #6. However the exhaust port through 2-3 shift solenoid is larger than orifice #6 to prevent a pressure increase in the 2-3 signal fluid circuit.