With the gear selector lever in the Park (P) position and the engine running, line pressure from the oil pump assembly is directed to the following:

Pressure Regulator Valve: Regulates pump output into line pressure in response to throttle signal fluid pressure, orificed line pressure and spring force. It directs this line pressure into both the converter in and suction fluid circuits.

Torque Converter Clutch Control Valve: Held in the release position by spring force, it directs converter in fluid into the release fluid circuit. Also, fluid returning from the converter through the apply fluid circuit is routed through the valve and into the cooler fluid circuit.

TCC Apply Checkball: Located in the turbine shaft, this ball is unseated by release fluid flowing to the torque converter. Release fluid quickly fills the converter and keeps the pressure plate in a released position.

Cooler and Lubrication Circuits: Cooler fluid from the TCC control valve is routed through the transmission fluid cooler and into the main case lube circuit. The overdrive lube circuit is fed by converter in fluid through an orifice (#3c/6) and provides lubrication for the components in the adapter case.

Spiral Capillary Restriction: Located in the adapter case, it reduces overdrive lube at very low temperatures. Reducing overdrive lube increases the fluid flow to the converter, cooler and main case lube circuits.

Overrun Clutch Applied

Overrun Lockout Valve: Held in the open position by spring force, this valve directs orificed line pressure into the overrun clutch fluid circuit. The orifice in the line pressure circuit (#2h) helps control the apply feel of the overrun clutch.

Overrun Clutch Piston: Overrun clutch fluid pressure moves the piston to apply the overrun clutch plates.

Line Pressure Tap: Located in the side of the converter housing, it provides access to monitor line pressure.

Manual Valve: Controlled by the selector lever, it is in the Park (P) position and blocks line pressure from entering any other fluid circuits.

Mode Switch (Electrical): Located on the selector shaft (61), it signals the TCM that the selector lever and manual valve are in the Park (P) position.

Shift Solenoids: The 1-2/3-4 shift solenoid is OFF and the 2-3 shift solenoid in ON. However, with the manual valve in the Park position and line pressure blocked by the valve, fluid is not fed to the shift solenoids and they are ineffective.

Force Motor Screen: Located in the adapter case valve body, it filters line pressure that feeds the feed limit valve and force motor solenoid.

Feed Limit Valve: Limits feed limit fluid pressure to a maximum range of 659 kPa to 765 kPa (96 psi to 111 psi). When line pressure is below this limiting value, feed limit fluid pressure equals line pressure.

Force Motor Solenoid: Controlled by the TCM, it regulates feed limit fluid into throttle signal fluid pressure in relation to throttle position and other vehicle operating conditions.

Throttle Signal Accumulator Piston: Controlled by spring force, it dampens any pressure irregularities in the throttle signal fluid circuit.

3-4 Accumulator Valve Train: Regulates line pressure into the 3-4 accumulator fluid circuit in relation to throttle signal fluid pressure, orificed 3-4 accumulator fluid pressure and, on some models, a 3-4 accumulator valve spring (408).

3-4 Accumulator Piston: 3-4 Accumulator fluid pressure fills the accumulator assembly and assists spring force in preparation for a 3-4 upshift.

Park - Engine Running