Hydraulic Operation

Line pressure hydraulic circuits:

• Line pressure from the pump is supplied to the main pressure regulator valve, low reverse/456 regulator valve, manual valve, solenoid regulator valve and control pressure regulator.
• Line pressure is controlled by the position of the main pressure regulator valve.
• The position of the main pressure regulator valve is controlled by varying pressure from the LPC solenoid through the VBS LINE circuit.

Torque converter circuits:

• Regulated line pressure from the main pressure regulator valve is directed to the TCC control valve through the CONV FD hydraulic circuit.
• When the TCC is released, CONV FD pressure is directed to the TCC RELEASE circuit by the TCC control valve. Pressure from the TCC RELEASE circuit releases the TCC.
• Fluid from the TCC RELEASE returns to the TCC control valve through the TCC APPLY circuit.

Cooler and lubrication hydraulic circuits:

• The TCC control valve directs fluid from the TCC APPLY circuit (return circuit from the torque converter when the TCC is released) to the COOLER FD circuit.
• In the COOLER FD circuit, transmission fluid flows through the transmission fluid cooler or the thermal bypass valve to the LUBE circuit in the input shaft to supply lubrication to the transaxle.

Solenoid hydraulic circuits:

• The LPC solenoid applies varying pressure to the main pressure regulator valve through the VBS LINE hydraulic circuit. The LPC solenoid regulates line pressure by controlling the position of the main pressure regulator valve.
• SSA applies pressure to the 1234 regulator and latch valves to apply the forward (1, 2, 3, 4) clutch.
• SSC applies pressure to the 26 regulator and latch valves to apply the intermediate (2, 6) clutch.

Clutch hydraulic circuits:

• Line pressure is supplied to the 1234 regulator valve by the manual valve in the DRIVE and LOW position. To apply the forward (1, 2, 3, 4) clutch, SSA supplies varying solenoid pressure to the 1234 regulator and latch valves. As the regulator valve moves, it supplies the forward (1, 2, 3, 4) clutch and 1234 latch valve with regulated line pressure through the C1234 circuit. The 1234 latch valve directs the regulated line pressure to the opposite side of the regulator valve through the C1234 FDBK circuit for gradual forward (1, 2, 3, 4) clutch engagement.
• Line pressure is supplied to the 26 regulator valve by the manual valve in the DRIVE and LOW positions. To apply the intermediate (2, 6) clutch, SSC supplies varying solenoid pressure to the 26 regulator and latch valves. As the 26 regulator valve moves, it supplies the intermediate (2, 6) clutch and 26 latch valve with regulated line pressure through the CB26 circuit. The 26 latch valve directs the regulated line pressure to the opposite side of the 26 regulator valve through the CB26 FDBK circuit for gradual intermediate (2, 6) clutch engagement.

For additional hydraulic circuit and information, refer to HYDRAULIC CIRCUITS  in this service information.